Bilic made the comments following the Hammers’ victory over Manchester City away from home in the Premier League on Saturday evening.
Sakho scored West Ham’s second goal of the match just past the half-hour mark, as the London outfit registered a remarkable 2-1 win in Manchester.
Following the game, Bilic spoke highly of the Senegal international striker, who joined the Hammers from French club Metz in the summer of 2014.
“Sakho is a great player," the Croatian told West Ham’s official website. "Some strikers have to score goals to prove their game.
"If they don't score they are not playing, but Diafra doesn't just have to score goals to play well. When you defend like he does when we don't have the ball, if anyone deserved the victory it was him.”
Sakho scored 10 goals and created 23 chances in 23 Premier League appearances for West Ham last season.
So far this campaign, the 25-year-old Hammers star has scored two goals and created as many chances in six league games.
Against City at the Etihad on Saturday evening, Sakho took two shots, put in two crosses, attempted three dribbles, and made two clearances and one block.