The lawyer of a young Sydney man jailed for life in Thailand for possession of ecstasy says the Australian had no drugs on his person when he was arrested.

Jake Mastroianni, 26, was arrested with Englishman Lance Whitmore in the tourist city of Pattaya in 2014 and received a double life sentence. That sentence was upheld on appeal in a Bangkok court on Wednesday.

Whitmore was found in possession of 200 ecstasy pills during an undercover police operation. He then led police to an apartment of Mastroianni's girlfriend, where they found another 61 pills and subsequently charged Mastroianni, who had been working as a DJ in Thailand.

Mastroianni's sentence was harsher than the 50 years Whitmore received, because unlike the Englishman, he refused to plead guilty.

Mastroianni's Bangkok-based lawyer, Nathan Feeney of the firm Thailand Bail, said the Australian was deeply unfortunate because there was still doubt about whether the ecstasy he was charged over in fact belonged to him.

"Jake was not in possession of the drugs, that's the important part," Mr Feeney said.

"The police were given information that led them to the girlfriend's apartment and Jake was there when they raided the apartment."

Mr Feeney said that because of poor legal advice Mastroianni received when he was first arrested and charged, the two quantities of pills were then combined for the indictment, which led to the Australian being charged with possession of 261 pills and exposed him to a life sentence.

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Lawyer working on transfer to Australian prison

Mr Feeney, speaking on behalf of Mastroianni's family, said the Sydney man was coping well with yesterday's decision.

"In the months leading up to the judgement, he has been managing his expectations," Mr Feeney said.

"He's done really well in prison, made the friends he needed to make, avoided confrontation.

"Going into the appeal he said he was not expecting anything at all.

"Half of the battle is the mental battle, and that's how he managed.

"The question is how do we get him back to Australia more quickly.

"We're currently considering all options but leaning towards working on the prisoner transfer to Australia."

Prisoners who receive a life sentence must serve eight years before being eligible for a transfer, but Mastroianni has already served two, meaning he must wait six years before becoming eligible for a return to Australia.

Mastroianni is being held in Bangkok's Klong Prem high security prison, which houses a large number of foreign prisoners.