Romelu Lukaku was subjected to monkey chants from the crowd during Inter Milan's 2-1 Serie A victory over Cagliari on Sunday.
The chants could be heard before and after the striker scored a penalty to win the game in his second appearance for the club.
The on-loan Manchester United player looked towards the Cagliari supporters after dispatching his spot-kick in the 72nd minute.
Former Juventus striker Moise Kean, as well as midfielder Blaise Matuidi, were subjected to racist chanting from Cagliari supporters during a Serie A clash last April.
The league's disciplinary panel later decided not to take action against the club.
Inter Milan, Cagliari and Serie A have yet to make any comment following the incident.