diff --git a/src/food-market.api/Controllers/Inventory/StockController.cs b/src/food-market.api/Controllers/Inventory/StockController.cs
index 6f25edc..f22b396 100644
--- a/src/food-market.api/Controllers/Inventory/StockController.cs
+++ b/src/food-market.api/Controllers/Inventory/StockController.cs
@@ -24,6 +24,7 @@ public record StockRow(
     public async Task<ActionResult<PagedResult<StockRow>>> GetStock(
         [FromQuery] Guid? storeId,
         [FromQuery] Guid? productId,
+        [FromQuery] Guid? groupId,
         [FromQuery] string? search,
         [FromQuery] bool includeZero = false,
         [FromQuery] int page = 1,
@@ -40,6 +41,11 @@ public record StockRow(
 
         if (storeId.HasValue) q = q.Where(x => x.s.StoreId == storeId.Value);
         if (productId.HasValue) q = q.Where(x => x.s.ProductId == productId.Value);
+        if (groupId.HasValue)
+        {
+            var groupIds = await DescendantGroupIdsAsync(groupId.Value, ct);
+            q = q.Where(x => groupIds.Contains(x.p.ProductGroupId));
+        }
         if (!includeZero) q = q.Where(x => x.s.Quantity != 0);
         if (!string.IsNullOrWhiteSpace(search))
         {
@@ -111,6 +117,19 @@ public record StockRow(
     public record StockExportRow(string Name, string? Article, string Unit, string Store,
         decimal Quantity, decimal Reserved, decimal Available);
 
+    /// <summary>Id группы + всех её вложенных подгрупп (по денормализованному
+    /// Path). Пустой список, если группа не найдена → фильтр вернёт пусто.</summary>
+    private async Task<List<Guid>> DescendantGroupIdsAsync(Guid groupId, CancellationToken ct)
+    {
+        var path = await _db.ProductGroups.Where(g => g.Id == groupId)
+            .Select(g => g.Path).FirstOrDefaultAsync(ct);
+        if (string.IsNullOrEmpty(path))
+            return await _db.ProductGroups.Where(g => g.Id == groupId).Select(g => g.Id).ToListAsync(ct);
+        return await _db.ProductGroups
+            .Where(g => g.Path == path || g.Path.StartsWith(path + "/"))
+            .Select(g => g.Id).ToListAsync(ct);
+    }
+
     public record MovementRow(
         Guid Id, DateTime OccurredAt,
         Guid ProductId, string ProductName, string? Article,