A six-year-old boy was hospitalized Friday night after falling from the third-floor window of his Bronx apartment building as his father was installing an air conditioner, police said.

The window screen and guard had been temporarily removed when the child tumbled from the Bailey Avenue apartment in Kingsbridge about 7:10 p.m., cops said.

He landed on a mulch-covered garden, cops said.

Witnesses said the boy was crying following the fall.

The youngster was taken to a nearby hospital in stable condition, police said, adding the incident appears to be an accident.

Building superintendent, Samuel Flores, 54, said the boy’s mom looked distressed following the incident.

As she hailed a cab to the Hospital, Flores said, “She looked nervous. She looked very, very nervous.