Hugh Glass, 57, was apprehended at Phuket's Sea Pearl Villas in Patong yesterday after an approach from the Serious Organised Crime Agency.
SOCA officer Jonathan King contacted Phuket Immigration on April 4 and told them he believed Glass, named in an international arrest warrant, was on Phuket.
According to Immigration records, Glass arrived on Phuket this visit on February 18.
He has in the past worked for hotels and resorts and is alleged to have abused one New Zealand child and two young Australian boys since arriving in Thailand in mid-2011.
He is also wanted in Britain for several convictions for sexual abuse of children. Glass had been sentenced in his absence to a total of 20 years in jail.
His record in Britain dates back to 1972, when he served 15 months for child abuse. Other crimes were alleged to have been committed in 1982, 1989, 1990 and 2001.
A court in Malta found him not guilty of one offence but he was accused in Malta again in 2006 and fled in 2010 after serving his sentence.
Extradition proceedings are likely to take place quickly, as they have done with previous arrests on Phuket involving international suspects.
It's understood charges will not be pressed for the alleged offences in Thailand.