diff --git a/WebContent/WEB-INF/view/productionplanning/prodPlanFormPopup.jsp b/WebContent/WEB-INF/view/productionplanning/prodPlanFormPopup.jsp
index 0a8f429..264cc5f 100644
--- a/WebContent/WEB-INF/view/productionplanning/prodPlanFormPopup.jsp
+++ b/WebContent/WEB-INF/view/productionplanning/prodPlanFormPopup.jsp
@@ -28,9 +28,32 @@
 .readonly-field {
 	background-color: #eee !important;
 }
+
+/* S/N 입력 필드 placeholder 색상 */
+#SERIAL_NO::placeholder {
+	color: #999 !important;
+	opacity: 1;
+}
+#SERIAL_NO::-webkit-input-placeholder {
+	color: #999 !important;
+}
+#SERIAL_NO::-moz-placeholder {
+	color: #999 !important;
+	opacity: 1;
+}
+#SERIAL_NO:-ms-input-placeholder {
+	color: #999 !important;
+}
+#SERIAL_NO {
+	cursor: pointer;
+}
 </style>
 </head>
 <script>
+// S/N 관리 변수
+var snList = [];
+var snCounter = 1;
+
 $(function(){
 	fnc_datepick();
 	$(".select2").select2();
@@ -43,6 +66,30 @@ $(function(){
 		fn_save();
 	});
 	
+	// S/N 클릭 시 팝업 오픈
+	$("#SERIAL_NO").click(function() {
+		fn_openSnManagePopup();
+	}).attr("placeholder", "클릭하여 S/N 추가").attr("readonly", true);
+	
+	// 페이지 로드 시 기존 S/N 데이터가 있으면 파싱
+	var initialSnValue = $("#SERIAL_NO").val();
+	if(initialSnValue && initialSnValue.trim() != '') {
+		var snArray = initialSnValue.split(',');
+		var initialSnList = [];
+		for(var i = 0; i < snArray.length; i++) {
+			if(snArray[i].trim() != '') {
+				initialSnList.push({
+					id: i + 1,
+					value: snArray[i].trim()
+				});
+			}
+		}
+		if(initialSnList.length > 0) {
+			snList = initialSnList;
+			snCounter = initialSnList.length + 1;
+		}
+	}
+	
 	// 프로젝트번호 변경 시 관련 정보 자동 로드 (Select2 이벤트)
 	$("#PROJECT_NO").on("change select2:select", function(){
 		var projectObjid = $(this).val();
@@ -377,6 +424,216 @@ function fn_save(){
 		});
 	}
 }
+
+// ========== S/N 관리 함수 ==========
+
+// S/N 관리 팝업 열기
+function fn_openSnManagePopup() {
+	// 기존 데이터 로드
+	var serialNoValue = $("#SERIAL_NO").val();
+	if(serialNoValue && serialNoValue.trim() != '' && snList.length == 0) {
+		var snArray = serialNoValue.split(',');
+		for(var i = 0; i < snArray.length; i++) {
+			if(snArray[i].trim() != '') {
+				snList.push({
+					id: snCounter++,
+					value: snArray[i].trim()
+				});
+			}
+		}
+	}
+	
+	// 팝업 HTML 생성
+	var popupHtml = '<div style="padding:10px; color:#333;">';
+	popupHtml += '	<h3 style="margin:0 0 15px 0; text-align:center; color:#333;">S/N 관리</h3>';
+	popupHtml += '	<div id="snListContainer" style="margin-bottom:15px; max-height:300px; overflow-y:auto; color:#333;"></div>';
+	popupHtml += '	<div style="margin-bottom:15px; display:flex; gap:5px;">';
+	popupHtml += '		<input type="text" id="newSnInput" placeholder="S/N 입력" style="flex:1; padding:8px; border:1px solid #ddd; border-radius:4px; color:#333;">';
+	popupHtml += '		<button type="button" onclick="fn_addSn()" class="plm_btns">추가</button>';
+	popupHtml += '	</div>';
+	popupHtml += '	<div style="text-align:center; margin-top:20px; display:flex; gap:10px; justify-content:center;">';
+	popupHtml += '		<button type="button" onclick="fn_openSequentialSnPopup()" class="plm_btns">연속번호생성</button>';
+	popupHtml += '		<button type="button" onclick="fn_confirmSnList()" class="plm_btns">확인</button>';
+	popupHtml += '		<button type="button" onclick="fn_closeSnPopup()" class="plm_btns">취소</button>';
+	popupHtml += '	</div>';
+	popupHtml += '</div>';
+	
+	// 팝업 오픈
+	Swal.fire({
+		html: popupHtml,
+		width: '700px',
+		showConfirmButton: false,
+		showCloseButton: true,
+		didOpen: function() {
+			setTimeout(function() {
+				fn_renderSnList();
+				// 엔터키로 추가
+				$("#newSnInput").keypress(function(e) {
+					if(e.which == 13) {
+						fn_addSn();
+						return false;
+					}
+				});
+			}, 50);
+		}
+	});
+}
+
+// S/N 목록 렌더링
+function fn_renderSnList() {
+	var html = '<table style="width:100%; margin-bottom:10px; border-collapse:collapse; border:1px solid #ddd; color:#333;">';
+	html += '<colgroup><col width="15%"><col width="65%"><col width="20%"></colgroup>';
+	html += '<thead><tr style="background:#f5f5f5; color:#333;">';
+	html += '<th style="padding:10px; border:1px solid #ddd; text-align:center; color:#333;">번호</th>';
+	html += '<th style="padding:10px; border:1px solid #ddd; text-align:center; color:#333;">S/N</th>';
+	html += '<th style="padding:10px; border:1px solid #ddd; text-align:center; color:#333;">삭제</th>';
+	html += '</tr></thead>';
+	html += '<tbody>';
+	
+	if(snList.length == 0) {
+		html += '<tr><td colspan="3" style="text-align:center; padding:30px; color:#999; border:1px solid #ddd;">등록된 S/N이 없습니다.</td></tr>';
+	} else {
+		for(var i = 0; i < snList.length; i++) {
+			html += '<tr>';
+			html += '<td style="text-align:center; padding:8px; border:1px solid #ddd; color:#333;">' + (i+1) + '</td>';
+			html += '<td style="padding:8px; border:1px solid #ddd; color:#333;">' + snList[i].value + '</td>';
+			html += '<td style="text-align:center; padding:8px; border:1px solid #ddd;">';
+			html += '<button type="button" onclick="fn_deleteSn(' + snList[i].id + ')" class="plm_btns" style="padding:5px 10px; font-size:12px;">삭제</button>';
+			html += '</td>';
+			html += '</tr>';
+		}
+	}
+	html += '</tbody></table>';
+	
+	$("#snListContainer").html(html);
+}
+
+// S/N 추가
+function fn_addSn() {
+	var newSn = $("#newSnInput").val().trim();
+	if(newSn == '') {
+		Swal.fire("S/N을 입력해주세요.");
+		return;
+	}
+	
+	// 중복 체크
+	for(var i = 0; i < snList.length; i++) {
+		if(snList[i].value == newSn) {
+			Swal.fire("이미 등록된 S/N입니다.");
+			return;
+		}
+	}
+	
+	snList.push({
+		id: snCounter++,
+		value: newSn
+	});
+	
+	$("#newSnInput").val('');
+	fn_renderSnList();
+}
+
+// S/N 삭제
+function fn_deleteSn(id) {
+	for(var i = 0; i < snList.length; i++) {
+		if(snList[i].id == id) {
+			snList.splice(i, 1);
+			break;
+		}
+	}
+	fn_renderSnList();
+}
+
+// S/N 목록 확인 및 적용
+function fn_confirmSnList() {
+	var snValues = [];
+	for(var i = 0; i < snList.length; i++) {
+		snValues.push(snList[i].value);
+	}
+	
+	$("#SERIAL_NO").val(snValues.join(', '));
+	Swal.close();
+}
+
+// S/N 팝업 닫기
+function fn_closeSnPopup() {
+	Swal.close();
+}
+
+// 연속번호 생성 팝업
+function fn_openSequentialSnPopup() {
+	var seqHtml = '<div style="padding:10px; color:#333;">';
+	seqHtml += '<h3 style="margin:0 0 15px 0; text-align:center; color:#333;">연속번호 생성</h3>';
+	seqHtml += '<table style="width:100%; border-collapse:collapse;">';
+	seqHtml += '<tr><td style="padding:8px; text-align:right; width:30%;">접두어:</td>';
+	seqHtml += '<td style="padding:8px;"><input type="text" id="seqPrefix" style="width:100%; padding:5px;" placeholder="예: SN-"></td></tr>';
+	seqHtml += '<tr><td style="padding:8px; text-align:right;">시작번호:</td>';
+	seqHtml += '<td style="padding:8px;"><input type="number" id="seqStart" style="width:100%; padding:5px;" value="1"></td></tr>';
+	seqHtml += '<tr><td style="padding:8px; text-align:right;">종료번호:</td>';
+	seqHtml += '<td style="padding:8px;"><input type="number" id="seqEnd" style="width:100%; padding:5px;" value="10"></td></tr>';
+	seqHtml += '<tr><td style="padding:8px; text-align:right;">자릿수:</td>';
+	seqHtml += '<td style="padding:8px;"><input type="number" id="seqDigits" style="width:100%; padding:5px;" value="3" min="1" max="10"></td></tr>';
+	seqHtml += '</table>';
+	seqHtml += '<div style="text-align:center; margin-top:15px;">';
+	seqHtml += '<button type="button" onclick="fn_generateSequentialSn()" class="plm_btns">생성</button>';
+	seqHtml += '<button type="button" onclick="fn_closeSeqPopup()" class="plm_btns" style="margin-left:10px;">취소</button>';
+	seqHtml += '</div></div>';
+	
+	Swal.fire({
+		html: seqHtml,
+		width: '400px',
+		showConfirmButton: false,
+		showCloseButton: true
+	});
+}
+
+// 연속번호 생성
+function fn_generateSequentialSn() {
+	var prefix = $("#seqPrefix").val();
+	var start = parseInt($("#seqStart").val()) || 1;
+	var end = parseInt($("#seqEnd").val()) || 10;
+	var digits = parseInt($("#seqDigits").val()) || 3;
+	
+	if(start > end) {
+		Swal.fire("시작번호가 종료번호보다 클 수 없습니다.");
+		return;
+	}
+	
+	if(end - start > 999) {
+		Swal.fire("한 번에 1000개 이상 생성할 수 없습니다.");
+		return;
+	}
+	
+	for(var i = start; i <= end; i++) {
+		var numStr = String(i).padStart(digits, '0');
+		var newSn = prefix + numStr;
+		
+		// 중복 체크
+		var isDup = false;
+		for(var j = 0; j < snList.length; j++) {
+			if(snList[j].value == newSn) {
+				isDup = true;
+				break;
+			}
+		}
+		
+		if(!isDup) {
+			snList.push({
+				id: snCounter++,
+				value: newSn
+			});
+		}
+	}
+	
+	Swal.close();
+	fn_openSnManagePopup();
+}
+
+// 연속번호 팝업 닫기
+function fn_closeSeqPopup() {
+	Swal.close();
+	fn_openSnManagePopup();
+}
 </script>
 <body>
 <form name="form1" id="form1" method="post">