The boy was discovered unconscious inside the apartment on Richman Plaza in the Morris Heights section of the Bronx at 8:30 p.m. on Wednesday.
He was rushed to Bronx Lebanon Hospital, where he was pronounced dead.
Detectives believe he climbed on a stand to change the TV channel, but slipped. His shirt apparently got caught on a bed post and choked the boy.
Detectives are interviewing the boy's mother, but no criminality is suspected.
There are four other children in the household and no there is no history with the Administration for Children's Services.