diff --git a/src/api/rooms/postPassword.ts b/src/api/rooms/postPassword.ts
new file mode 100644
index 00000000..ef5cbbe1
--- /dev/null
+++ b/src/api/rooms/postPassword.ts
@@ -0,0 +1,23 @@
+import { apiClient } from '../index';
+
+export interface PostPasswordRequest {
+  password: string;
+}
+
+export interface PostPasswordResponse {
+  isSuccess: boolean;
+  code: number;
+  message: string;
+  data: {
+    matched: boolean;
+    roomId: number;
+  };
+}
+
+export const postPassword = async (
+  roomId: number,
+  data: PostPasswordRequest,
+): Promise<PostPasswordResponse> => {
+  const response = await apiClient.post<PostPasswordResponse>(`/rooms/${roomId}/password`, data);
+  return response.data;
+};
diff --git a/src/components/group/PasswordModal.tsx b/src/components/group/PasswordModal.tsx
new file mode 100644
index 00000000..09291765
--- /dev/null
+++ b/src/components/group/PasswordModal.tsx
@@ -0,0 +1,226 @@
+import React, { useState, useRef, useEffect } from 'react';
+import styled from '@emotion/styled';
+import { colors, typography } from '@/styles/global/global';
+import leftArrow from '@/assets/common/leftArrow.svg';
+import TitleHeader from '@/components/common/TitleHeader';
+import { useNavigate } from 'react-router-dom';
+import { postPassword } from '@/api/rooms/postPassword';
+import { postJoinRoom } from '@/api/rooms/postJoinRoom';
+import { usePopupActions } from '@/hooks/usePopupActions';
+
+interface PasswordModalProps {
+  roomId: number;
+}
+
+const PasswordModal = ({ roomId }: PasswordModalProps) => {
+  const [password, setPassword] = useState<string[]>(['', '', '', '']);
+  const [activeIndex, setActiveIndex] = useState<number>(0);
+  const [errorMessage, setErrorMessage] = useState<string>('');
+  const inputRefs = useRef<(HTMLInputElement | null)[]>([]);
+  const navigate = useNavigate();
+  const { openSnackbar } = usePopupActions();
+
+  // 컴포넌트 마운트 시 상태 초기화
+  useEffect(() => {
+    setPassword(['', '', '', '']);
+    setActiveIndex(0);
+    setErrorMessage('');
+  }, []);
+
+  // 입력 필드 포커스 관리
+  useEffect(() => {
+    if (inputRefs.current[activeIndex]) {
+      inputRefs.current[activeIndex]?.focus();
+    }
+  }, [activeIndex]);
+
+  useEffect(() => {
+    if (errorMessage) {
+      const timer = setTimeout(() => {
+        setErrorMessage('');
+      }, 1500);
+
+      return () => clearTimeout(timer);
+    }
+  }, [errorMessage]);
+
+  const handleClickBack = () => {
+    navigate(-1);
+  };
+
+  // 비밀번호 확인 API 호출
+  const handlePasswordConfirm = async (fullPassword: string) => {
+    setErrorMessage('');
+
+    try {
+      // 1. 비밀번호 확인 API 호출
+      const passwordResponse = await postPassword(roomId, { password: fullPassword });
+
+      if (passwordResponse.isSuccess && passwordResponse.data.matched) {
+        // 2. 비밀번호가 맞으면 방 참가 API 호출
+        const joinResponse = await postJoinRoom(roomId, 'join');
+
+        if (joinResponse.isSuccess) {
+          // 성공 후 처리 (방 상세 페이지로 이동)
+          navigate(`/group/detail/${roomId}`);
+          // 성공 snackbar 표시
+          openSnackbar({
+            message: '모임방 참여가 완료되었어요! 모집 마감 후 활동이 시작돼요.',
+            variant: 'top',
+            onClose: () => {},
+          });
+        } else {
+          // 실패 후 처리 (방 상세 페이지로 이동)
+          navigate(`/group/detail/${roomId}`);
+          // 실패 snackbar 표시
+          openSnackbar({
+            message: '모임방 참여에 실패했어요. 다시 시도해 주세요.',
+            variant: 'top',
+            onClose: () => {},
+          });
+        }
+      } else {
+        setErrorMessage('비밀번호가 일치하지 않습니다.');
+        // 비밀번호 입력 필드 초기화
+        setPassword(['', '', '', '']);
+        setActiveIndex(0);
+      }
+    } catch {
+      setErrorMessage('오류가 발생했습니다. 다시 시도해주세요.');
+      // 비밀번호 입력 필드 초기화
+      setPassword(['', '', '', '']);
+      setActiveIndex(0);
+    }
+  };
+
+  const handleInputChange = (index: number, value: string) => {
+    // 숫자만 입력 허용
+    if (!/^\d*$/.test(value)) return;
+
+    const newPassword = [...password];
+    newPassword[index] = value;
+    setPassword(newPassword);
+
+    // 다음 입력 필드로 이동
+    if (value && index < 3) {
+      setActiveIndex(index + 1);
+    }
+
+    // 4자리 모두 입력 완료 시 자동으로 비밀번호 확인
+    if (newPassword.every(digit => digit !== '') && index === 3) {
+      const fullPassword = newPassword.join('');
+      handlePasswordConfirm(fullPassword);
+    }
+  };
+
+  const handleKeyDown = (index: number, e: React.KeyboardEvent<HTMLInputElement>) => {
+    if (e.key === 'Backspace') {
+      if (password[index] === '') {
+        // 현재 필드가 비어있으면 이전 필드로 이동
+        if (index > 0) {
+          setActiveIndex(index - 1);
+          const newPassword = [...password];
+          newPassword[index - 1] = '';
+          setPassword(newPassword);
+        }
+      } else {
+        // 현재 필드 내용 삭제
+        const newPassword = [...password];
+        newPassword[index] = '';
+        setPassword(newPassword);
+      }
+    }
+  };
+
+  const handleInputClick = (index: number) => {
+    setActiveIndex(index);
+  };
+
+  return (
+    <Overlay>
+      <TitleHeader
+        leftIcon={<img src={leftArrow} alt="뒤로 가기" />}
+        onLeftClick={handleClickBack}
+      />
+      <Title>비밀번호를 입력해주세요.</Title>
+      <PasswordInputContainer>
+        {password.map((digit, index) => (
+          <PasswordInput
+            key={index}
+            ref={(el: HTMLInputElement | null) => {
+              inputRefs.current[index] = el;
+            }}
+            type="text"
+            value={digit}
+            onChange={e => handleInputChange(index, e.target.value)}
+            onKeyDown={e => handleKeyDown(index, e)}
+            onClick={() => handleInputClick(index)}
+            maxLength={1}
+            inputMode="numeric"
+            hasError={!!errorMessage}
+          />
+        ))}
+      </PasswordInputContainer>
+      {errorMessage && <ErrorMessage>{errorMessage}</ErrorMessage>}
+    </Overlay>
+  );
+};
+
+export default PasswordModal;
+
+const Overlay = styled.div`
+  position: fixed;
+  top: 0;
+  left: 0;
+  right: 0;
+  bottom: 0;
+  min-width: 320px;
+  max-width: 767px;
+  min-height: 100vh;
+  background-color: ${colors.black.main};
+  margin: 0 auto;
+  display: flex;
+  flex-direction: column;
+  align-items: center;
+  z-index: 2000;
+`;
+
+const Title = styled.div`
+  color: ${colors.white};
+  font-size: ${typography.fontSize.lg};
+  font-weight: ${typography.fontWeight.semibold};
+  line-height: 24px;
+  letter-spacing: 0.018px;
+  text-align: center;
+  margin-top: 217px;
+`;
+
+const PasswordInputContainer = styled.div`
+  display: flex;
+  gap: 12px;
+  margin-top: 32px;
+`;
+
+const PasswordInput = styled.input<{ hasError: boolean }>`
+  width: 44px;
+  height: 44px;
+  border-radius: 12px;
+  background-color: ${colors.darkgrey.main};
+  border: ${props => (props.hasError ? `1px solid ${colors.red}` : 'none')};
+  outline: none;
+
+  text-align: center;
+  color: ${colors.white};
+  caret-color: ${colors.neongreen};
+  font-family: ${typography.fontFamily.secondary};
+  font-size: ${typography.fontSize.lg};
+  font-weight: ${typography.fontWeight.semibold};
+  line-height: normal;
+`;
+
+const ErrorMessage = styled.div`
+  color: ${colors.red};
+  font-size: ${typography.fontSize.sm};
+  text-align: center;
+  margin-top: 12px;
+`;