diff --git a/packages/react-bootstrap-table2/src/header-cell.js b/packages/react-bootstrap-table2/src/header-cell.js
index 2053453..79b4b9b 100644
--- a/packages/react-bootstrap-table2/src/header-cell.js
+++ b/packages/react-bootstrap-table2/src/header-cell.js
@@ -49,6 +49,7 @@ const HeaderCell = (props) => {
 
   if (headerStyle) {
     cellStyle = _.isFunction(headerStyle) ? headerStyle(column, index) : headerStyle;
+    cellStyle = cellStyle ? { ...cellStyle } : cellStyle;
   }
 
   if (headerTitle) {