Former Wakefield MP Imran Ahmad Khan lost his case when he was found guilty of sexual assault.
Khan, who was Wakefield’s Conservative MP from 2019 until his resignation in April, was jailed for 18 months in May after he was found guilty of assaulting a 15-year-old boy at a house in 2008.
He has denied the allegations.
The 49-year-old challenged his conviction in the Court of Appeals last month.
On Monday, the appeal was dismissed with judge Michael Sweeney saying he had “no doubt” that Khan’s trial was fair and that his sentence was safe.