A woman was fatally struck by a yellow cab after she fell out of another taxi on the Upper East Side early Wednesday morning, police said.

The unidentified woman, who is believed to be homeless, was in a taxi traveling south on Lexington Avenue when she opened the rear passenger door and fell onto the street, between East 69th and East 68th streets, at about 5 a.m., police said.

She was then run over by another taxi, also traveling south on Lexington Avenue, according to police.

Both drivers fled the scene, cops said.

The woman was pronounced dead at an area hospital.

The driver of the first taxi was later arrested and charged with leaving the scene of an accident and reckless endangerment. Police were still looking for the other driver.