diff --git a/frontend/src/components/PostForm/CategoryWrapper/index.tsx b/frontend/src/components/PostForm/CategoryWrapper/index.tsx
index 6362d8714..d744de40b 100644
--- a/frontend/src/components/PostForm/CategoryWrapper/index.tsx
+++ b/frontend/src/components/PostForm/CategoryWrapper/index.tsx
@@ -6,6 +6,8 @@ import { useCategoryList } from '@hooks/query/category/useCategoryList';
 import MultiSelect from '@components/common/MultiSelect';
 import { Option } from '@components/common/MultiSelect/types';
 
+import { POST_CATEGORY } from '@constants/policy';
+
 import { changeCategoryToOption } from '@utils/post/changeCategoryToOption';
 
 interface CategoryWrapperProps {
@@ -30,6 +32,7 @@ export default function CategoryWrapper({ multiSelectHook }: CategoryWrapperProp
       handleOptionAdd={handleOptionAdd}
       handleOptionDelete={handleOptionDelete}
       placeholder="카테고리를 선택해주세요."
+      maxOptionCount={POST_CATEGORY.MAX_AMOUNT}
     />
   );
 }
diff --git a/frontend/src/components/PostForm/index.tsx b/frontend/src/components/PostForm/index.tsx
index 6cc60a01a..17a153e45 100644
--- a/frontend/src/components/PostForm/index.tsx
+++ b/frontend/src/components/PostForm/index.tsx
@@ -68,11 +68,7 @@ export default function PostForm({ data, mutate, isSubmitting }: PostFormProps)
 
   const categorySelectHook = useMultiSelect(categoryIds ?? [], POST_CATEGORY.MAX_AMOUNT);
   const { text: writingTitle, handleTextChange: handleTitleChange } = useText(title ?? '');
-  const {
-    text: writingContent,
-    handleTextChange: handleContentChange,
-    addText: addContent,
-  } = useText(content ?? '');
+  const { text: writingContent, handleTextChange: handleContentChange } = useText(content ?? '');
   const writingOptionHook = useWritingOption(
     serverVoteInfo?.options.map(option => ({
       ...option,
diff --git a/frontend/src/components/common/MultiSelect/index.tsx b/frontend/src/components/common/MultiSelect/index.tsx
index bf47f35d4..19150808f 100644
--- a/frontend/src/components/common/MultiSelect/index.tsx
+++ b/frontend/src/components/common/MultiSelect/index.tsx
@@ -15,6 +15,7 @@ interface MultiSelectProps {
   handleOptionAdd: (newItem: Option) => void;
   handleOptionDelete: (optionId: number) => void;
   placeholder?: string;
+  maxOptionCount?: number;
 }
 
 export default function MultiSelect({
@@ -22,6 +23,7 @@ export default function MultiSelect({
   optionList,
   handleOptionAdd,
   handleOptionDelete,
+  maxOptionCount,
   placeholder = '여러 개의 옵션을 선택해주세요',
 }: MultiSelectProps) {
   const [isOpen, setIsOpen] = useState(false);
@@ -35,6 +37,15 @@ export default function MultiSelect({
     setIsOpen(!isOpen);
   };
 
+  const addOption = ({ id, name }: Option) => {
+    handleOptionAdd({ id, name });
+
+    // selectedOptionList.length 는 추가되기 이전의 값
+    if (maxOptionCount && selectedOptionList.length + 1 >= maxOptionCount) {
+      setIsOpen(false);
+    }
+  };
+
   const handleOutsideClick = (event: MouseEvent) => {
     if (wrapperRef.current && !wrapperRef.current.contains(event.target as Node)) {
       setIsOpen(false);
@@ -90,7 +101,7 @@ export default function MultiSelect({
               aria-label={`클릭시 ${name} 추가`}
               onClick={e => {
                 e.stopPropagation();
-                handleOptionAdd({ id, name });
+                addOption({ id, name });
               }}
             >
               {name}
diff --git a/frontend/src/hooks/useMultiSelect.ts b/frontend/src/hooks/useMultiSelect.ts
index c032641a5..3151c0c0f 100644
--- a/frontend/src/hooks/useMultiSelect.ts
+++ b/frontend/src/hooks/useMultiSelect.ts
@@ -1,15 +1,19 @@
-import { useState } from 'react';
+import { useContext, useState } from 'react';
 
 import type { Option } from '@components/common/MultiSelect/types';
 
+import { ToastContext } from './context/toast';
+
 export const useMultiSelect = (initialSelectedOptionList: Option[], optionCountLimit?: number) => {
   const [selectedOptionList, setSelectedOptionList] = useState(initialSelectedOptionList);
+  const { addMessage } = useContext(ToastContext);
 
   const handleOptionAdd = (newItem: Option) => {
     if (optionCountLimit && optionCountLimit === selectedOptionList.length) {
-      alert(`${optionCountLimit}개까지 선택 가능합니다!`);
+      addMessage(`${optionCountLimit}개까지 선택 가능합니다!`);
       return;
     }
+
     setSelectedOptionList([...selectedOptionList, newItem]);
   };