The 25-year-old has been one of the Hammers standout performers this season, helping the east London outfit move into 11th place in the Premier League table.
Diamé has scored two goals in 16 Premier League appearances after joining on a free transfer from Wigan Athletic in the summer.
And Allardyce envisages the midfielder playing a big part in West Ham’s future, with the Hammers boss not considering cashing in on the Senegal star.
“He won’t go anywhere,” Allardyce told the Times.
“He likes it here. [His improvement] is down to the challenge he’s taken on. The size of a club demands a certain size of performance and we’re a sell-out club, with 35,000 people, great tradition. He’s responded.
“We changed his role. The ability he has to break through the opposition’s midfield is rare. Other players have to pass their way through.
“That’s why West Ham fans love him, those long, penetrating, weavey runs. He gets into the positions so often that if we can work on the finishing and final pass we could be talking about a really top player.”