Son Heung-Min was subjected to "utterly reprehensible" online racist abuse, Tottenham said on Sunday.
The Premier League club called for social media companies to take action after Son was targeted during the 2-0 win against West Ham United.
The forward scored four minutes after coming on as a second-half substitute.
After the match, Spurs posted on Twitter: "We have been made aware of the utterly reprehensible online racist abuse directed at Heung-Min Son during today's match, which has been reported by the club.
"We stand with Sonny and once again call on the social media companies and authorities to take action."
Anti-racism group Kick It Out earlier this month demanded "meaningful reforms" after Brentford striker Ivan Toney was subjected to racial abuse on Instagram.
The abuse occurred after Toney's controversial equaliser against Arsenal, which should have been ruled out by VAR for offside against teammate Christian Norgaard.
Toney also revealed in October last year that he had been targeted on Instagram after scoring both goals in a 2-0 league victory over Brighton.