Thais eat a lot of meat! Therefor it is not the easiest thing to find vegetarian food outside the tourist places! You can always ask for it and they will try their best to cook something vegetarian for you, but very often they are not used to. To avoid misunderstandings do not just only tell them that you eat vegetarian but also tell them not to add pork, chicken, fish, shrimps etc. ONLY vegetables (and eggs, tofu etc.). It will be more easy if you accept at least fish-sauce - otherwise your menu may be a little boring. Look for the food markets - there you will always find a lot of delicious meatless dishes and fingerfood!

"mangsawirat" is the thai word for vegetarian. or you can say "may say nuea sat" = without meat. or "may say bla, may say gung" = without fish, without shrimps.

i travelled for quite a long time in thailand and never hab any problems with beeing a vegetarian. there even is a very nice 100 % vegetarian restaurant near the main train station next to the underground exit, can't remember the name, but i think it's listed in lonely planet ... i really enjoyed the food there!

You might try to order food with the expression kin jay or phom kin jay which me often helps out to avoid some unwanted ingredients.

maykaidee is the best vegetarian restaurant in bangkok! there are at least 3 of them. sam saen soi 1, khao san and sorry, don#t know the third.