diff --git a/backend/handlers/cart_handler.go b/backend/handlers/cart_handler.go
index 57f347f..7540f60 100644
--- a/backend/handlers/cart_handler.go
+++ b/backend/handlers/cart_handler.go
@@ -1,6 +1,8 @@
 package handlers
 
 import (
+	"fmt"
+	"math"
 	"net/http"
 
 	"github.com/gin-gonic/gin"
@@ -27,6 +29,13 @@ func GetCart(c *gin.Context) {
 	c.JSON(http.StatusOK, cartItems)
 }
 
+func isValidQuantity(item models.Item, quantity float64) bool {
+	if item.UnitType == "piece" {
+		return quantity == math.Trunc(quantity)
+	}
+	return true
+}
+
 func AddToCart(c *gin.Context) {
 	userID := getUserID(c)
 
@@ -47,6 +56,10 @@ func AddToCart(c *gin.Context) {
 		return
 	}
 
+	if !isValidQuantity(item, req.Quantity) {
+		c.JSON(http.StatusBadRequest, gin.H{"error": fmt.Errorf("товар %s продается поштучно, дробное количество недопустимо", item.Name)})
+	}
+
 	if req.Quantity > item.Stock {
 		c.JSON(http.StatusBadRequest, gin.H{"error": "Недостаточно товара на складе"})
 	}
diff --git a/backend/handlers/item_handlers.go b/backend/handlers/item_handlers.go
index d0aab1f..2dc9317 100644
--- a/backend/handlers/item_handlers.go
+++ b/backend/handlers/item_handlers.go
@@ -68,29 +68,35 @@ func UpdateItem(c *gin.Context) {
 	}
 
 	database.DB.Model(&item).Updates(models.Item{
-		Name:  input.Name,
-		Unit:  input.Unit,
-		City:  input.City,
-		Price: input.Price,
+		Name:     input.Name,
+		Unit:     input.Unit,
+		UnitType: input.UnitType,
+		City:     input.City,
+		Price:    input.Price,
 	})
 
 	c.JSON(http.StatusOK, item)
 }
 
 func AddItem(c *gin.Context) {
-	var input models.Item
+	var item models.Item
 
-	if err := c.ShouldBindJSON(&input); err != nil {
+	if err := c.ShouldBindJSON(&item); err != nil {
 		c.JSON(http.StatusBadRequest, gin.H{"error": "Неверные данные"})
 		return
 	}
 
-	if err := database.DB.Create(&input).Error; err != nil {
+	if item.UnitType != "weight" && item.UnitType != "piece" {
+		c.JSON(http.StatusBadRequest, gin.H{"error": "Товар должен быть весовым или штучным"})
+		return
+	}
+
+	if err := database.DB.Create(&item).Error; err != nil {
 		c.JSON(http.StatusInternalServerError, gin.H{"error": "Не удалось создать товар"})
 		return
 	}
 
-	c.JSON(http.StatusCreated, input)
+	c.JSON(http.StatusCreated, item)
 }
 
 func DeleteItem(c *gin.Context) {
diff --git a/backend/models/item.go b/backend/models/item.go
index de4cd18..8c5339f 100644
--- a/backend/models/item.go
+++ b/backend/models/item.go
@@ -7,6 +7,7 @@ type Item struct {
 	Name      string    `json:"name"`
 	City      string    `json:"city"`
 	Unit      string    `json:"unit"`
+	UnitType  string    `json:"unit_type" gorm:"default:'weight'"`
 	Price     int       `json:"price"`
 	Category  string    `json:"category"`
 	Stock     float64   `gorm:"default:0" json:"stock"`