Ex-Knick Chris Copeland is suing the Chelsea hotspot 1Oak where he was stabbed last year after arguing with a fellow club-goer.

Copeland was partying at the W. 17th Street nightclub on April 8, 2015 with fellow NBA player Thabo Sefolosha when he got into an argument with Shevoy Bleary-Murdock as he was leaving 1Oak around 4 a.m.

The criminal case against Bleary-Murdock is still pending but Copeland and his former girlfriend Katrina Saltara — who was also stabbed — are suing the club, saying security allowed the slasher to bring a spring-operated switchblade into the premises and then failed to immediately intervene during the attack.

Copeland had surgery on his abdomen and elbow while Saltara has permanent scars.

The suit, seeking unspecified damages, was filed in Manhattan Supreme Court Thursday just weeks after the Milwaukee Bucks cut Copeland from its roster.

Earlier this week, Sefolosha sued cops over his arrest.

A rep for the club did not return a request for comment.

Copeland’s attorney, Alex Spiro, declined to comment because of the pending criminal case.