Valencia has been out injured for the entirety of the Premier League season to date, but Bilic is looking forward to having the Ecuadorian forward back available to him.
"He's one of our biggest weapons on the pitch," he told Sky Sports. "He's looking sharp and very good. Now it is just a matter of fitness and slowly getting him in shape to be fit."
Valencia was brought to West Ham in the summer of 2014, and he showed his pace and power during his first campaign at Upton Park.
The forward was a menace to defences across the league, but he struggled to put an end product on all the promise that he showed.
Valencia scored just five times during the 2014/15 campaign, and his task this time around will be to ensure that total increases.
Valencia's return to West Ham's forward-line will bolster Bilic's options in an area which has already been a real strength of his side.
The Hammers have netted 17 times in the Premier League to date, meaning only Manchester City have been more free-scoring than Bilic's men.