Oxford was loaned out by West Ham towards the back end of last season to Reading, but he did not gain much first-team experience.
The Hammers then sent him on a temporary move to Germany this term, with the youngster joining up with Borussia Monchengladbach.
However, Oxford is yet to make an appearance in the Bundesliga, and that has led to concerns that the 18-year-old’s development could be stalling.
West Ham fans are now worried that Oxford may see his path to the first-team blocked by new additions.
But Bilic insists that he believes Oxford will become a first-team player for the Hammers next term.
"He needed to go somewhere to play more regularly, he is at a good club but unfrtunately he is still waiting," Bilic said.
"He is very positive and I expect him to get in their starting line up soon and come back to West Ham and be a regular player for us."
Oxford burst on to the scene as a 16-year-old, when he was given his first-team chance, and his performances were highly impressive.
Bilic has been more restrained with utilising the youngster in recent times though - with Oxford making just two appearances for the Hammers last term.
If Oxford does return to West Ham next term, he will be in competition with the likes of Jose Fonte, Angelo Ogbonna and Winston Reid for a starting role.