The 20-year-old full-back, on loan at German club Hoffenheim from Tottenham, late on Monday night shared a screengrab of an abusive message he had been sent on social media and said he was “not even surprised any more”.
He wrote on an Instagram story: “Honestly unbelievable. The craziest thing is I’m not even surprised any more. Disgusting.”
Spurs showed support to their player on Tuesday morning, posting on Twitter: “Everyone at the club is with you @RyanSessegnon.
“We are proud of the rich ethnic diversity that exists across our communities, fans, staff and players.
“We are driven by inclusion and equality for all and nobody should have to endure such repulsive abuse.”
Hoffenheim also condemned the “horrific” abuse.
“Today, our player @RyanSessegnon was the target of horrific online racist abuse.
“#TSG stands for tolerance, integration and respect. We reject all forms of racism, discrimination and exclusion and say #NoToRacism!
Crystal Palace’s Wilfried Zaha and Manchester City’s Raheem Sterling are among other players to reveal they have been targeted.
Ivory Coast international Zaha was sent racist messages and imagery in July and a 12-year-old boy was arrested in connection with the incident.
England forward Sterling last month questioned whether there was the will among social media companies to combat online abuse towards footballers after a study highlighted the shocking extent of the problem.
More than 3,000 explicitly abusive messages were sent publicly via Twitter over the six-week Project Restart period to 44 high-profile players currently or formerly involved in English football, research showed.
Forty three per cent of the Premier League players in the study (13 out of 30) experienced targeted and explicitly racist abuse, while three players who called out racism during the period – Sterling, Zaha and Wycombe’s Adebayo Akinfenwa – received 50 per cent of all the abuse.