Peter Root and Mary Thompson, both 34, were killed when hit by the pickup truck while cycling on the Route 304 Phnom Sarakam-Kabinburi Road in this eastern province.
Police Lt-Col Supachai Loangsukcharoen said the bodies of the couple are being kept at a charity association in the province pending their family's collection. The British embassy has contacted the local authorities to bring their bodies back to the UK.
Col Supachai said driver Worapong Sangkhawat, 25, who was seriously injured in the crash, has been released on bail after posting Bt300,000 bail bond.
A police investigation team are collecting evidence to charge him for dangerous driving leading to others' death. If found guilty, he could face a maximum penalty of 10 years in jail
The Guernsey couple set off on a round-the-world adventure in July 2011 and had cycled through Europe, the Middle East and China.
The British newspaper the Telegraph quoted a British Foreign Office spokesperson as saying that "We are aware of the deaths of two British nationals in Thailand on February 13 and we are providing consular assistance."
On their website, Two on Four Wheels, the couple posted a travel journal, photographs and short films from the 23 countries they had visited.