The two culprits walked up to the 73-year-old man at the junction of Pearl Street and Bradford Road at around 1.30pm on Tuesday, March 22, while he was waiting for a bus.
One of the men, who were both white, asked if the victim could change some coins and presented money from his pocket.
The elderly man, from Birstall, agreed and the two exchanged cash – but on returning home he realised the thug had pulled his wedding ring from his finger.
PC Darren Hill, of Heckmondwike Police, said: “We are appealing for witnesses to this offence in which the victim has had his wedding ring stolen on what, by a terrible turn of fate, was his 50th wedding anniversary.
“Clearly this would have been an extremely upsetting offence for the victim at any time of year but for it to happen on his 50th wedding anniversary has only made the circumstances even more upsetting.
“I would ask anyone who saw this offence or may be able to help us identify these two men to come forward.
“We would also advise residents in the Batley area to be wary of this kind of scam.”
The first suspect was described as 6ft tall, fat and balding with a lump under his right eye. He also had an eastern European accent.
The second man was white, 5ft 6ins tall, slim, and also had an olive complexion.
Anyone who has information should contact PC Hill at the Batley NPT on 101, quotingcrime number 1316026319. Information can also be given anonymously to the Independent Crimestoppers charity on 0800 555 111.