Thailand doesn't have large homegrown criminal organizations. At least not compared to something like the Triads in Hong Kong and Taiwan, the Yakuza in Japan, Jopok/Kkangpae in South Korea or the so-called "Black Societies" in Vietnam.

There are however lots of transnational criminal organizations from all over the world - mostly from East Asia, Europe and Oceania - operating in Thailand and all of them launder a lot of money in Thailand. In that way Thailand is like the Spain of Asia. And there are of course plenty of crooked businessmen and politicians in Thailand who know about these operations and are able to line their pockets with it.