A city school bus driver showed no mercy toward a child who begged to stop at a restroom, telling the 11-year-old boy to “just pee yourself,” he and his livid mom told The Post.

Shannon O’Grady, an administrator with the city Department of Education, said her sixth-grade son, John, called her Thursday on his 90-minute bus ride from a special-ed school in Manhattan to the Bronx.

“Mommy, I have to use the bathroom so bad, it really hurts,” he cried.

When he told the female bus driver, John said, she replied: “You’re gonna have to wait,” and “It’s okay to pee yourself.”

O’Grady then asked her son to put the matron on the phone, and offered to get in her car and meet the bus en route to pick him up.

“‘There’s nothing we can do,’” O’Grady said the matron replied. “They demonstrated a complete lack of compassion.”

Meanwhile, John refused to suffer the embarrassment of soiling himself.

“I just tried to avoid the bumps,” he said. “I was trying to sit still and not move. It was painful.”

John was the last of five kids on the bus to be dropped off, and ran into his house — where O’Grady held the door open for him.

“I’m over it now, but I was really sad and angry when it happened,” he said.

O’Grady filed a complaint with the DOE’s Office of Pupil Transportation, and asked that the driver and matron be switched to a different route. An OPT customer-service representative said it couldn’t be done: “That’s just policy.”

But DOE spokeswoman Miranda Barbot told The Post, “We suspended this driver while we conduct a thorough investigation of this deeply troubling allegation.”

Sources said bus companies generally tell drivers not to stop for children to use a rest room because they don’t want employees to be accused of touching kids inappropriately.