Jamal Campbell-Ryce will be released by parent club Bristol City.
The 29-year-old has made six starts for Leyton Orient since rejoining the Brisbane Road side on loan in March, with one further appearance from the bench.
Saturday saw the former Charlton Athletic man once again link well with O’s top scorer Kevin Lisbie as he netted his first goal for the club since his return.
He has featured a further 18 times in all competitions for the Robins this term but manager Derek McInnes has opted not to offer him a new contract.
Campbell-Ryce will now leave Ashton Gate in the summer in search of a new club.