On 9 August 2015, Kouyaté scored the opening goal in the 43rd minute in a 2–0 win over Arsenal at the Emirates Stadium. He then scored in a 4–3 home defeat to AFC Bournemouth on 22 August. He scored his third goal of the season in a 2–2 draw with Norwich City on 26 September, netting the equalizer in the 90th minute to rescue a point for West Ham. In March 2016, Kouyate signed a new, five-year contract with West Ham that could keep him at the club until 2021. Kouyaté was sent-off twice during the 2015–16 season and on both occasions had the card rescinded by The Football Association (FA). On 21 February, he was dismissed by referee Jonathan Moss in a 5–1 FA Cup win at Blackburn Rovers, only for the card to be rescinded a few days later. On 2 April, he was dismissed in a Premier League game at the Boleyn Ground against Crystal Palace by referee Mark Clattenburg. This too, however, was overturned a few days later.