diff --git a/backend/src/main/java/com/magistr/app/controller/GroupController.java b/backend/src/main/java/com/magistr/app/controller/GroupController.java
index b8f7795..0365aea 100755
--- a/backend/src/main/java/com/magistr/app/controller/GroupController.java
+++ b/backend/src/main/java/com/magistr/app/controller/GroupController.java
@@ -32,6 +32,7 @@ public class GroupController {
                 .map(g -> new GroupResponse(
                         g.getId(),
                         g.getName(),
+                        g.getGroupSize(),
                         g.getEducationForm().getId(),
                         g.getEducationForm().getName()))
                 .toList();
@@ -45,6 +46,9 @@ public class GroupController {
         if (groupRepository.findByName(request.getName().trim()).isPresent()) {
             return ResponseEntity.badRequest().body(Map.of("message", "Группа с таким названием уже существует"));
         }
+        if (request.getGroupSize() == null) {
+            return ResponseEntity.badRequest().body(Map.of("message", "Численность группы обязательна"));
+        }
         if (request.getEducationFormId() == null) {
             return ResponseEntity.badRequest().body(Map.of("message", "Форма обучения обязательна"));
         }
@@ -56,12 +60,14 @@ public class GroupController {
 
         StudentGroup group = new StudentGroup();
         group.setName(request.getName().trim());
+        group.setGroupSize(request.getGroupSize());
         group.setEducationForm(efOpt.get());
         groupRepository.save(group);
 
         return ResponseEntity.ok(new GroupResponse(
                 group.getId(),
                 group.getName(),
+                group.getGroupSize(),
                 group.getEducationForm().getId(),
                 group.getEducationForm().getName()));
     }
diff --git a/backend/src/main/java/com/magistr/app/dto/CreateGroupRequest.java b/backend/src/main/java/com/magistr/app/dto/CreateGroupRequest.java
index 43e604a..dfbe5a0 100755
--- a/backend/src/main/java/com/magistr/app/dto/CreateGroupRequest.java
+++ b/backend/src/main/java/com/magistr/app/dto/CreateGroupRequest.java
@@ -3,6 +3,7 @@ package com.magistr.app.dto;
 public class CreateGroupRequest {
 
     private String name;
+    private Long groupSize;
     private Long educationFormId;
 
     public String getName() {
@@ -13,6 +14,14 @@ public class CreateGroupRequest {
         this.name = name;
     }
 
+    public Long getGroupSize() {
+        return groupSize;
+    }
+
+    public void setGroupSize(Long groupSize) {
+        this.groupSize = groupSize;
+    }
+
     public Long getEducationFormId() {
         return educationFormId;
     }
diff --git a/backend/src/main/java/com/magistr/app/dto/GroupResponse.java b/backend/src/main/java/com/magistr/app/dto/GroupResponse.java
index 63becb8..7dd7c58 100755
--- a/backend/src/main/java/com/magistr/app/dto/GroupResponse.java
+++ b/backend/src/main/java/com/magistr/app/dto/GroupResponse.java
@@ -4,12 +4,14 @@ public class GroupResponse {
 
     private Long id;
     private String name;
+    private Long groupSize;
     private Long educationFormId;
     private String educationFormName;
 
-    public GroupResponse(Long id, String name, Long educationFormId, String educationFormName) {
+    public GroupResponse(Long id, String name, Long groupSize, Long educationFormId, String educationFormName) {
         this.id = id;
         this.name = name;
+        this.groupSize = groupSize;
         this.educationFormId = educationFormId;
         this.educationFormName = educationFormName;
     }
@@ -22,6 +24,10 @@ public class GroupResponse {
         return name;
     }
 
+    public Long getGroupSize() {
+        return groupSize;
+    }
+
     public Long getEducationFormId() {
         return educationFormId;
     }
diff --git a/backend/src/main/java/com/magistr/app/model/StudentGroup.java b/backend/src/main/java/com/magistr/app/model/StudentGroup.java
index 3ad914a..9deee86 100755
--- a/backend/src/main/java/com/magistr/app/model/StudentGroup.java
+++ b/backend/src/main/java/com/magistr/app/model/StudentGroup.java
@@ -13,6 +13,9 @@ public class StudentGroup {
     @Column(unique = true, nullable = false, length = 100)
     private String name;
 
+    @Column(name = "group_size", nullable = false)
+    private Long groupSize;
+
     @ManyToOne(optional = false)
     @JoinColumn(name = "education_form_id", nullable = false)
     private EducationForm educationForm;
@@ -36,6 +39,14 @@ public class StudentGroup {
         this.name = name;
     }
 
+    public Long getGroupSize() {
+        return groupSize;
+    }
+
+    public void setGroupSize(Long groupSize) {
+        this.groupSize = groupSize;
+    }
+
     public EducationForm getEducationForm() {
         return educationForm;
     }
diff --git a/db/init/init.sql b/db/init/init.sql
index d55142b..3c3339b 100755
--- a/db/init/init.sql
+++ b/db/init/init.sql
@@ -43,14 +43,16 @@ ON CONFLICT (name) DO NOTHING;
 CREATE TABLE IF NOT EXISTS student_groups (
     id BIGSERIAL PRIMARY KEY,
     name VARCHAR(100) UNIQUE NOT NULL,
+    group_size BIGINT NOT NULL,
     education_form_id BIGINT NOT NULL REFERENCES education_forms(id),
     course INT CHECK (course BETWEEN 1 AND 6),
     created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
 );
 
 -- Тестовая базовая группа для работы
-INSERT INTO student_groups (name, education_form_id, course) 
-VALUES ('ИВТ-21-1', 1, 3) 
+INSERT INTO student_groups (name, group_size, education_form_id, course)
+VALUES ('ИВТ-21-1', 25, 1, 3),
+       ('ИБ-41м', 15, 2, 2)
 ON CONFLICT (name) DO NOTHING;
 
 -- ==========================================
diff --git a/frontend/admin/js/views/groups.js b/frontend/admin/js/views/groups.js
index 1a2b1d6..17301b5 100755
--- a/frontend/admin/js/views/groups.js
+++ b/frontend/admin/js/views/groups.js
@@ -68,6 +68,7 @@ export async function initGroups() {
       <tr>
         <td>${g.id}</td>
         <td>${escapeHtml(g.name)}</td>
+        <td>${escapeHtml(g.groupSize)}</td>
         <td><span class="badge badge-ef">${escapeHtml(g.educationFormName)}</span></td>
         <td><button class="btn-delete" data-id="${g.id}">Удалить</button></td>
       </tr>`).join('');
@@ -77,13 +78,15 @@ export async function initGroups() {
         e.preventDefault();
         hideAlert('create-group-alert');
         const name = document.getElementById('new-group-name').value.trim();
+        const groupSize = document.getElementById('new-group-size').value;
         const educationFormId = newGroupEfSelect.value;
 
         if (!name) { showAlert('create-group-alert', 'Введите название группы', 'error'); return; }
+        if (!groupSize) { showAlert('create-group-alert', 'Введите размер группы', 'error'); return; }
         if (!educationFormId) { showAlert('create-group-alert', 'Выберите форму обучения', 'error'); return; }
 
         try {
-            const data = await api.post('/api/groups', { name, educationFormId: Number(educationFormId) });
+            const data = await api.post('/api/groups', { name, groupSize, educationFormId: Number(educationFormId) });
             showAlert('create-group-alert', `Группа "${escapeHtml(data.name)}" создана`, 'success');
             createGroupForm.reset();
             loadGroups();
diff --git a/frontend/admin/js/views/users.js b/frontend/admin/js/views/users.js
index 921991b..00aad8c 100755
--- a/frontend/admin/js/views/users.js
+++ b/frontend/admin/js/views/users.js
@@ -79,8 +79,19 @@ export async function initUsers() {
 
     // Заполнение select группами
     function renderGroupOptions() {
+        if (!groups || groups.length === 0) {
+            lessonClassroomSelect.innerHTML = '<option value="">Нет доступных групп</option>';
+            return;
+        }
+
         lessonGroupSelect.innerHTML = '<option value="">Выберите группу</option>' +
-            groups.map(g => `<option value="${g.id}">${escapeHtml(g.name)}</option>`).join('');
+            groups.map(g => {
+            let optionText = escapeHtml(g.name);
+            if(g.groupSize) {
+                optionText += ` (численность: ${g.groupSize} чел.)`;
+            }
+            return `<option value="${g.id}">${optionText}</option>`;
+            }).join('');
     }
 
     // Заполнение select дисциплинами
@@ -90,10 +101,40 @@ export async function initUsers() {
     }
 
     function renderClassroomsOptions() {
+        if (!classrooms || classrooms.length ===0) {
+            lessonClassroomSelect.innerHTML = '<option value="">Нет доступных аудиторий</option>';
+            return;
+        }
+
+        const selectedGroupId = lessonGroupSelect.value;
+        const selectedGroup = groups?.find(g => g.id == selectedGroupId);
+        const groupSize = selectedGroup?.groupSize || 0;
+
         lessonClassroomSelect.innerHTML = '<option value="">Выберите аудиторию</option>' +
-            classrooms.map(c => `<option value="${c.id}">${escapeHtml(c.name)}</option>`).join('');
+            classrooms.map(c => {
+            let optionText = escapeHtml(c.name);
+            // Добавление текста с инфой о вместимости чел.
+            if(c.capacity) {
+                optionText += ` (вместимость: ${c.capacity} чел.)`;
+            }
+
+            // Если аудитория занята, то рисуем крестик допом
+            if (c.isAvailable === false) {
+                optionText += ` ❌ Занята`
+            // Если свободна, но меньше численности группы, отображаем воскл. знак
+            } else if (selectedGroupId && groupSize > 0 && c.capacity && groupSize > c.capacity) {
+                optionText += ` ⚠️ Недостаточно места`;
+            }
+
+
+            return `<option value="${c.id}">${optionText}</option>`;
+            }).join('');
     }
 
+    lessonGroupSelect.addEventListener('change', function() {
+        renderClassroomsOptions();
+    });
+
     // NEW: функция обновления списка времени в зависимости от дня
     function updateTimeOptions(dayValue) {
         let times = [];
diff --git a/frontend/admin/views/groups.html b/frontend/admin/views/groups.html
index 2dc558c..5944cdc 100755
--- a/frontend/admin/views/groups.html
+++ b/frontend/admin/views/groups.html
@@ -7,6 +7,10 @@
                 <label for="new-group-name">Название группы</label>
                 <input type="text" id="new-group-name" placeholder="ИВТ-21-1" required>
             </div>
+            <div class="form-group">
+                <label for="new-group-size">Численность группы</label>
+                <input type="text" id="new-group-size" placeholder="20" required>
+            </div>
             <div class="form-group">
                 <label for="new-group-ef">Форма обучения</label>
                 <select id="new-group-ef">
@@ -35,6 +39,7 @@
                 <tr>
                     <th>ID</th>
                     <th>Название</th>
+                    <th>Численность (чел.)</th>
                     <th>Форма обучения</th>
                     <th>Действия</th>
                 </tr>