The summer signing from Metz has now hit the net seven times in eight games for the Hammers following his strike during Saturday's win over Manchester City.
Despite some doubts over whether he can maintain his form for the remainder of the campaign, Kouyate believes that Sakho will continue to be a danger up front for West Ham.
"I am really happy for him and I hope, for him, that he's going to continue like that," he told the club's official website. "Diafra's unreal, that's his level. He continues to surprise me and surprise everyone. I know very well that he can do better still and he's going to carry on scoring!"
West Ham continue their Premier League campaign this Saturday with a trip to Stoke City.