A CVS worker charged with stabbing a serial shoplifter to death during a fight inside a Midtown Manhattan store was only acting in self-defense, his mother claims.

Scotty Enoe, 46, is accused of fatally knifing the 50-year-old homeless man after the alleged thief socked him in the face inside the drug store at Broadway and West 49th Street early Thursday, cops and sources said.

“The guy came in and started arguing with Scotty. Next thing you know, Scotty was on the ground. He acted in self-defense,” the employee’s mom, Lucille Enoe, 72, told the Daily News.

“When the guy threw him down and started beating him up, Scotty stabbed him.”

The fatal scuffle broke out after Enoe had tried to stop the alleged would-be thief from trying to take off with Gatorade and a container of creamer just before 12:30 a.m., according to police and sources.

After being punched, Enoe allegedly whipped out a knife and fatally stabbed the man in the torso.

Police responded to reports of a robbery-in-progress but the stabbing had already unfolded.

“I feel very sad about the man even though he attacked my son,” Enoe’s mom, who said her son called her from the precinct, told the outlet.

“I feel sad that he died.”

Enoe, of Brooklyn, was taken into custody at the scene and later charged with murder and criminal possession of a weapon.

“It’s frustrating and depressing that my son has been charged. My son was defending himself,” his mom said.

Enoe’s sister, who didn’t give her name, added: “This guy attacked him. My brother is a good person. In a situation like that he would defend himself.”

Once in custody, the worker asked for a lawyer and wouldn’t make any statements to cops, law enforcement sources said.

The homeless man, who was pronounced dead at Bellevue Hospital, had more than a dozen previous shoplifting arrests to his name and was known to target drug stores in Upper Manhattan, according to sources.

“That’s his MO, he targets CVS and Walgreens,” a police source said.