The 25-year-old Senegalese striker was arrested on suspicion of domestic violence on Thursday, just days before the Premier League season opener against Arsenal.
Sakho managed to start against the Gunners, and performed admirably after being bailed until late September, and according to Bilic his motivation or attitude have not changed ahead of Saturday's home clash with Leicester City.
"He's training and he played against Arsenal, and he was here every day since," Bilic said.
"He looks okay. He looks happy and he is not worried. For all those things I am happy.
"For all the other aspects of this problem, you should talk to Diafra.
"I was concerned and spoke to him but he looks very positive and he is not worried about it. Therefore – as he trained normally this week – I am happy with him."