According to Thai law, foreigners can work in the country but factors such as the national security, as well as the need of alien labour for the development of the country are being considered. Thai nationals are still to be given priority.
Here is a list of the businesses that are prohibited to foreigners:
The Alien Business Law (N.E.C. Announcement 281). Business activities falling in categories A & B are generally closed to foreigners. Under category C you must obtain a permit prior to commencing business. Businesses outside these categories are exempt. The Ministry of Commerce will also help applications of non trading offices.
1. Agriculture: rice farming; salt farming.
2. Commercial Business: Internal trade in local agriculture products, Land trade.
3. Service business: Accounting, farming animals, architecture, advertising, brokerage, auctioning, Barber, hair dressing & beautician. Building industry.
1. Agriculture Business: orchids, cultivation, animal husbandry including silk worm raising, timbering, fishing.
2. Industrial & Handicraft: Rice milling, Flour making, sugar, alcohol & non alcohol drinks, Ice cream, Pharmaceutical manufacturing, cold storage, timber, gold, silver and inlaid stone, wood carving, lacquer-ware, match making, cement etc, Dynamiting rocks, Manufacturing garments & shoes, Printing, newspaper publishing, silk weaving or silk printing, manufacture of finished products in silk.
3. Commercial: all retailing not in category C. Or trading not in Category C, selling food an drinks, trading of antiques & fine arts.
4. Service Industry: Tour agency, Hotels except Hotel management, photography, laundering, dress making and service jobs.
5. Land, water & i.e. Transport.
You are allowed to do the following:
Exporting, all wholesale trades not in A & B. retiling machinery, equipment & tools, selling food, beverages that promote tourism. Industrial & handicraft Business: manufacturing animal feeds, vegetable oil extraction, textile manufacturing, dyeing, fabric printing, glass ware manufacturing, making plates and bowls, stationary & printing paper, rock salt mining, mining.
In the category, you have to apply for a work permit in order to do business legally in Thailand.