A bicycle-riding deliveryman was killed yesterday on the Upper East Side by an MTA bus that continued traveling on, authorities said.

The cyclist was heading south on Second Avenue near 96th Street just after 4 p.m. when he fell off his bike and was run over by the express bus, according to witnesses.

He was pronounced dead at the scene.

Sources said there does not appear to be criminality, but officials have yet to track down the bus.