diff --git a/plugins/table-merged-cell/src/js/renderer.js b/plugins/table-merged-cell/src/js/renderer.js
index 933385254d..4c8bb6b9a1 100644
--- a/plugins/table-merged-cell/src/js/renderer.js
+++ b/plugins/table-merged-cell/src/js/renderer.js
@@ -1,3 +1,5 @@
+import encodeHTMLEntity from 'tui-code-snippet/string/encodeHTMLEntity';
+
 export const renderer = {
   tableRow(node, { entering, origin }) {
     if (entering) {
@@ -47,7 +49,7 @@ export const renderer = {
       const { attributes = {} } = result;
 
       if (node.orgStringContent) {
-        attributes['data-org-content'] = node.orgStringContent;
+        attributes['data-org-content'] = encodeHTMLEntity(node.orgStringContent);
       }
       if (node.colspan) {
         attributes.colspan = node.colspan;
diff --git a/plugins/table-merged-cell/src/js/tableRenderer.js b/plugins/table-merged-cell/src/js/tableRenderer.js
index 76534d6b39..7e3a559f3d 100644
--- a/plugins/table-merged-cell/src/js/tableRenderer.js
+++ b/plugins/table-merged-cell/src/js/tableRenderer.js
@@ -2,6 +2,8 @@
  * @fileoverview Implements tableRenderer
  * @author NHN FE Development Lab <dl_javascript@nhn.com>
  */
+import encodeHTMLEntity from 'tui-code-snippet/string/encodeHTMLEntity';
+
 import tableDataHandler from './tableDataHandler';
 
 /**
@@ -27,7 +29,7 @@ function _createCellHtml(cell) {
 
   if (orgContent) {
     orgContent += content;
-    attrs += ` data-org-content="${orgContent}"`;
+    attrs += ` data-org-content="${encodeHTMLEntity(orgContent)}"`;
   }
 
   return `<${nodeName}${attrs}>${content}</${nodeName}>`;