Reports had suggested that Hernandez was struggling to be fit for Friday's Premier League meeting with Brighton & Hove Albion, but Bilic has claimed that the Mexican international should be available for the fixture at the London Stadium.
The 49-year-old told reporters: "Chicharito had a slight problem but he's training at 4pm and he should be good to train with us.
"It's not a big thing. He trained and felt a little bit of a tight hamstring, so we scanned it which was important, and the scan was completely clear. He missed Wednesday's light session and we expect him to train today and, based on his feeling, to be OK."
Hernandez has scored three goals in eight league appearances since moving to the Hammers from Bayer Leverkusen during the summer.