Hi, and welcome to LQ!
If your laptop overheats it can have several possible causes:
1. The cooling system isn't working to its fully extent, possibly due to dust. Solution would be to clean up the cooling system.
2. The power-saving features are not installed or configured correctly. To help you with that we need more information about your distribution and your machine.
3. A program is using the processor to 100% all the time. You can check that with the top-command or a system-information tool, if your desktop environment has one.