Tyrone Harbour caused the 14-week-old to sustain a fractured arm, and numerous bruises.
The 24 year old from Windmill Road in Hemel Hempstead, was sentenced at Oxford Crown Court yesterday.
He assaulted the baby in a property in Banbury in November 2015, and was charged the following October.
Police have described Harbour as a 'risk to the public.'
He was found guilty by a unanimous jury of one count of GBH with intent and one account of assault occasioning ABH.
Investigating officer Detective Constable Steven Gilks of the Child Abuse Investigation Unit, said: “Tyrone Harbour has been convicted of causing serious and harmful injuries to a baby.
“He has not accepted any responsibility for what he has done and only he knows the reason why he assaulted a 14-week-old baby.
“He is a risk to the public, and will now have time to reflect upon his actions in prison.”