A Manhattan courtroom is about to turn into a dog-fighting ring as the owner of a purse-size Havanese is suing the owner of hulking pit bull in a first-of-its-kind legal showdown.

The 8-pound pup, named Kinje, and her owner are demanding that a judge declare Luna the pit bull a “dangerous dog” and force the animal to wear a muzzle because of repeated attacks at their Chelsea apartment building.

“I was really lucky Kinje survived,” said her owner, Vivian Liu, who showed pictures of bloody bite marks on the little dog’s face and chest from one incident.

The suit mark’s the first time a dog owner has gone to court in New York to get a canine labeled dangerous, instead of the usual method of asking the Health Department to make such a declaration, according to Liu’s attorney, Richard Rosenthal.

Liu had gone to the department about Luna, but got no response, Rosenthal said. The Health Department did not respond to a request for comment.

“The level of aggression from that pit bull and the inability or unwillingness of its owners to control such dangerous behavior makes [Liu] terrified every time she leaves or returns to her building,” the suit says.

Manhattan Supreme Court Justice Joan Madden has granted a hearing next week. If she rules in Kinje’s favor, Luna will be muzzled and could face euthanization if she attacks again.

The suit comes about a year after Liu’s West 18th Street condo board hauled Luna and its owner, corporate attorney Michell Kelban, into court to have the dog evicted for attacking Kinje outside the building.

The incident, which left Kinje bloodied, was caught on video. But instead of leading to Luna’s removal, the case was settled with Kelban agreeing to muzzle the 60-pound dog.

But Liu said that little has changed, and that Luna still lunges and snarls at the Havanese, court papers charge.

“As soon as the pit bull saw . . . . Kinje it charged, growled and was lunging viciously as its owner tried to force the pit bull behind a mailbox,” the suit says.

Adam Leitman Bailey, attorney for Kelban and Luna, said state law prohibits Liu from filing a second case because she signed off on a confidential settlement in the first suit by the condo.