diff --git a/apps/api/src/app/order/create-order.dto.ts b/apps/api/src/app/order/create-order.dto.ts
index 49b193ca5..d4beff752 100644
--- a/apps/api/src/app/order/create-order.dto.ts
+++ b/apps/api/src/app/order/create-order.dto.ts
@@ -13,6 +13,7 @@ import {
   IsISO8601,
   IsNumber,
   IsOptional,
+  IsPositive,
   IsString
 } from 'class-validator';
 import { isString } from 'lodash';
@@ -51,6 +52,7 @@ export class CreateOrderDto {
   fee: number;
 
   @IsNumber()
+  @IsPositive()
   quantity: number;
 
   @IsString()
@@ -64,6 +66,7 @@ export class CreateOrderDto {
   type: Type;
 
   @IsNumber()
+  @IsPositive()
   unitPrice: number;
 
   @IsBoolean()
diff --git a/apps/api/src/app/order/update-order.dto.ts b/apps/api/src/app/order/update-order.dto.ts
index a8c33c40e..9dfe52e8d 100644
--- a/apps/api/src/app/order/update-order.dto.ts
+++ b/apps/api/src/app/order/update-order.dto.ts
@@ -13,6 +13,7 @@ import {
   IsISO8601,
   IsNumber,
   IsOptional,
+  IsPositive,
   IsString
 } from 'class-validator';
 import { isString } from 'lodash';
@@ -53,6 +54,7 @@ export class UpdateOrderDto {
   id: string;
 
   @IsNumber()
+  @IsPositive()
   quantity: number;
 
   @IsString()
@@ -66,5 +68,6 @@ export class UpdateOrderDto {
   type: Type;
 
   @IsNumber()
+  @IsPositive()
   unitPrice: number;
 }