An NYPD traffic cop punched her aunt in the face at a Thanksgiving gathering in the Bronx, police said Saturday.

Jazmine Knowles, 28, is facing an assault charge for the brawl, which started about 7:45 p.m. Thursday inside an apartment near Thieriot Avenue in Soundview, officials said.

The aunt, 31, had accused Knowles of hitting her son, although there wasn’t any evidence the boy had been abused, police said.

“Shut the f–k up,” Knowles spat back, then took aim at her aunt, police said. The aunt refused medical attention.

Knowles was arrested shortly after the fight, authorities said.

She makes $38,625 a year working for the NYPD, online records show.