Use the overflow property to hide overflowing content:
document.getElementById("myDiv").style.overflow = "hidden";
<!DOCTYPE html> <html> <head> <style> div {/*w ww . j av a 2s.c o m*/ border: 1px solid red; width: 100px; height: 100px; } </style> </head> <body> <div id="myDiv"> This is some text. This is some text. This is some text. This is some text. This is some text. This is some text. This is some text. This is some text. This is some text. </div> <br> <button type="button" onclick="myFunction()">Hide overflow</button> <script> function myFunction() { document.getElementById("myDiv").style.overflow = "hidden"; } </script> </body> </html>