There aren't any compulsory vaccinations you need for Thailand. However, whenever you travel you should make sure you are up-to-date on routine vaccines. These include measles-mumps-rubella, tetanus, chickenpox, polio, and your yearly flu shot. There are some vaccines that are recommended for travellers visiting Thailand, including typhoid and hepatitis A.
We advise that you speak with your doctor before your trip for appropriate advice.