A homeless man stabbed another vagrant outside of a Manhattan shelter in a fight over a woman on Thursday evening, police sources said.

The brawl kicked off at about 7 p.m. on 45th Street near Eighth Avenue in front of the Aladdin Hotel, a former inn that now houses about 300 homeless people, cops said.

The suspect pulled a blade during the fight and knifed a 31-year-old man in the stomach and the neck, cops said. Police believe they both live in the shelter.

The victim was rushed to Bellevue Hospital with serious injuries, but is expected to survive. The suspect ran off after the melee and is still at large, police said.

The dispute appears to be a beef over a woman, a police source told The Post.

Photos captured at the scene soon after the stabbing show a woman with blood smeared on her face, legs and arms speaking to NYPD detectives.