25-year-old Joseph Ulloa was arrested Tuesday night after a lengthy interview with police.
Porterville Police Officers say Ulloa lived with his baby in an apartment complex in east Porterville.
Last month, Ulloa called 9-1-1 saying the infant wasn't breathing. The baby was eventually transported to Children's Hospital of Central California in Fresno County. He remained there on life support for three weeks before he died.
Sgt. Jake Castellow said, "The first responding officers and the initial medical personnel there was no visible injuries to the child and it was later determined thru the hospital staff and the autopsy that it was internal head injuries."
Ulloa is expected to be arraigned on murder charges by Friday.