The Only Fools and Horses star will debut in the crime drama's tenth series, according to the Radio Times.
Original stars Amanda Redman and Alun Armstrong are both set to exit the programme, following the departure earlier this year of James Bolam (Jack Halford).
"I am thrilled to have been asked to join New Tricks," Lyndhurst said in a statement. "I have always admired the clever mixture of charm, wit and intelligence the show brings to its audience, and feel very flattered to be part of the BBC's top drama series."
Exec producer Richard Burrell added: "I think that the audience are going to have great fun watching him as a new member of the anarchic UCOS team, ensuring that solving cases for the Met is never dull. We can't wait to start working with him."
In addition to his famous role as Rodney Trotter on Only Fools and Horses, 51-year-old Lyndhurst has starred in BBC Two sitcom Butterflies and time-travel comedy Goodnight Sweetheart.
His most recent TV role was in Only Fools prequel Rock & Chips, in which he played Rodney's father Freddie 'The Frog' Robdal.
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