3 to 5 years.

The basic duration of a doctoral degree is 3 years, and the basic course time is about 1 year. The rest of the time is mainly about writing a thesis. If you pass the thesis, you can apply for graduation.

The application conditions for Ph.D. in Thailand are that the applicant must have graduated with a master's degree, be recommended by two associate professors or above, meet relevant English standards, or have a master's degree with excellent grades. The categories and conditions for accepting Chinese students are applicable.