To marry in Thailand, you have to first get into Thailand with a regular visitor’s visa or a Business Visa. You can also arrive with a VOA (Visa on Arrival) at the airport which gives you 30 days access to Thailand. Once there, you will have to find the rules and regulations of your own country (go to your own embassy in Bangkok) and prepare the paperwork to get a “freedom to marry” certificate stating that you have no prior obligations in your country.
Also find out how to make this wedding legal in your own country.
The second step is to go with your future partner to the local office called “Amphur” or “Khet”. Here, the foreign affidavits and clearance letters are translated, viewed and recognized before the couple is allowed to proceed to the district office for an Administrative Thailand Marriage. Once the papers are all validated and signed, you can live as a married couple anywhere in Thailand. You may also want to see the article on dowry in Thailand, getting a marriage visa and visa extensions in Thailand.