A homeless Bronx straphanger with nearly two dozen prior arrests allegedly beat and choked another vagrant to death after that man roused him from his sleep with a cane early Wednesday, prosecutors and sources said.

The homeless victim — identified by prosecutors as Cranston Smith — allegedly tapped snoozing stranger Keith Plummer, 68, with the cane on board a No. 1 train at the 242nd Street-Van Cortlandt Park Station around 3 a.m. Wednesday, law enforcement sources said.

The random contact sparked a brawl between the two men — with Plummer allegedly straddling Smith, punching him multiple times and grabbing and pressing on his neck, according to a complaint filed in Bronx Criminal Court.

Plummer at one point pinned his rival onto the floor of the stopped train at the northernmost stop on the line, the sources said.

The victim became unconscious and unresponsive, and was rushed to NewYork-Presbyterian Allen Hospital, where he died, police said.

Plummer was busted hours later and charged with manslaughter, cops said.

Plummer has 22 previous arrests on his record, the most recent for alleging forging a government document in February of 2019, police said.

Plummer was busted back in April of 2017 for allegedly shoving a 22-year-old man to the ground during a botched weed deal – during which he also snatched the stranger’s credit cards and demanded the PIN numbers, authorities said.

He also allegedly fought a police officer who stopped him for acting disorderly, causing the cop to fall down a flight of stairs back in 2007, police said.

Many of his other arrests have been for drug possession, cops said.

His most recent address provided by cops is in Jamaica, Queens, but law enforcement sources said he too is homeless.

He was ordered held on $200,000 cash bail or $600,000 bond during his Thursday arraignment and will reappear in court Monday, prosecutors said.