The Frenchman, who signed from Eintracht Frankfurt for £45million last summer, picked up a hip problem in the final week before the first game back from the Premier League's suspension, but is now back in training.
With games coming thick and fast - the Hammers now face three matches in six days so soon after their trip to Newcastle on Sunday - Moyes needs as many options as possible.
"Sebastien Haller is doing better," Moyes said ahead of Wednesday's meeting at the London Stadium. "We will see how he is once we finish today. He is getting closer. Whether he is ready to play is a different thing. Felipe Anderson won't be available for the game."
With Moyes having found a formula that seems to work, with the win over Chelsea and a point at Newcastle leaving them within touching distance of safety for another season, there is little reason to change much despite the packed schedule.
Having returned from a slight hamstring problem from the bench at the weekend, captain Mark Noble could return to midfield.
Predicted West Ham XI vs Burnley (4-1-4-1): Fabianski; Fredericks, Diop, Ogbonna, Cresswell; Rice; Bowen, Soucek, Noble, Fornals; Antonio