Karma’s a bitch.

An armed mugger — who had stolen cash from a victim on Long Island last night — was killed moments later when a car struck him as he walked along a busy thoroughfare, cops said.

The robber was struck by a 2004 Nissan Altima at 6 p.m. on Veterans Memorial Highway in Ronkonkoma. About 15 minutes before, the thug, whose name and age were not immediately released, held up someone at a nearby hotel.

Cops said they found the stolen cash and “parts of the gun” near the dead man’s body. No criminality was suspected in the accident.

Abdul Boustani, manager of the nearby Airport Diner, said cops told him they found $2,000 in cash and that the robber was part of a duo of stickup artists who had been suspected in other cases.

In a bizarre twist, allegedly drunken motorist Dominick Dimola was nabbed for passing by the accident scene traveling the wrong way on Veterans Highway as cops investigated the earlier incident.