An 11-year-old boy was arrested yesterday for bringing a loaded pistol to his Queens school, authorities said.

The boy arrived at PS 140 in Jamaica in the morning, and at about 8:30 a.m. he allegedly bragged to a pal that he was carrying a loaded pistol in his bookbag, cops said.

The frightened friend told a school-safety officer of the boast.

The safety officer searched the other boy’s bag and found the loaded Glock 9mm semi-automatic in it, according to cops and school officials.

The officer then confiscated the pistol, authorities said.

The 11-year-old, whose name was not disclosed because of his age, was arrested and taken to the 113th Precinct station house, according to police.

He was charged as a juvenile with criminal possession of a weapon.

Department of Education spokesman Margie Feinberg said the boy also faces disciplinary action from the school.