A 13-year-old boy was fighting for his life early Sunday after a hit-and-run driver ran into him in The Bronx and coldly fled the scene, cops said.

The teen, who was riding a blue bicycle, was struck near East 233rd Street and Jerome Avenue, near an entrance ramp to the Major Deegan Expressway around 9:30 p.m. Saturday, according to authorities.

“My friend was crossing and when [the driver] turned he hit him,” a young pal of the victim told The Post at the scene.

Cops said the gray sedan drove off without stopping.

Hours later, the youngster’s mangled bicycle was still lying on East 233rd Street, just outside Van Cortlandt Park.

The victim was taken to Jacobi Hospital in critical condition.