24 year old Jason Sherman of Cincinnatus is charged with Felony Manslaughter and Assault.
He's accused of causing the death of 16 month old Marshall Barber Junior last November.
The Chenango County Sheriff's debuties were called to a Town of Pitcher home, where they found the baby boy unresponsive.
An autopsy ruled his death a homicide, caused by blunt head trauma and asphyxiation.
Police say Sherman was the live-in boyfriend of the baby's mother.
He was arraigned in Chenango County Court and sent to the County Correctional facility on 500 thousand dollars bail.