This wasn’t the beer blast he expected.

A Cornell grad at the annual alumni reunion was injured when a beer can shot out of the frat-house bonfire “like a rocket” and hit him in the face.

Anthony Ventura, a 24-year-old Wall Streeter, is now suing his frat brother and fellow alum Connor Fitzpatrick, 25, a healthcare COO, over the kegger gone wrong.

Ventura and Fitzpatrick were attending a Delta Chi fraternity party at the Ithaca frat house on May 10, 2014, when a blitzed Fitzpatrick hurled an unopened can of beer into the fire, the lawsuit alleges.

“The can exploded and shot out like a rocket and hit him in the face,” said Barton Slavin, Ventura’s attorney.

The JPMorgan Chase wealth-management analyst suffered a concussion and “orthopedic and neurological damage” and was out of work “for awhile,” said Slavin.

Fitzpatrick said, “I’ll have to get back to you on that,” when reached last week for comment. He never did.

Ventura’s Manhattan Supreme Court suit, which seeks unspecified damages, also names the fraternity as a defendant.