A 57-year-old man was fatally mowed down by a school bus in Riverdale this morning, cops said.

The bus was heading south on Broadway when it plowed into the man as he crossed Moshulu Parkway at about 6 a.m., cops said.

The victim, Milo Montivilla, went into cardiac arrest and was rushed to St. Joseph’s Hospital in Yonkers, where he later died, officials said.

The bus driver stayed at the scene and was not charged with a crime, police said.