How do i change my time zone on facebook?

The times that you see on FB is linked to the time on your computer. So if you want to change your timezone you have to change the time on your cpu.

According to the official Facebook website, your time zone on Facebook will be set according to your computer’s time zone. To change your computer’s time zone, double-click on the "time’ located in the right-hand corner of your desktop screen, then select the "Time Zone" tab when the pop-up box appears. 

www.facebook.com/help/?page=808