The father, identified only as a Yemeni research scholar at Medina's Islamic University, was arrested last month, the Saudi Gazette reported Tuesday.
The maternal uncle of the 9-year-old said the father had used a variety of forms of torture on the boy, who has been identified only as Adel.
The child's family can ask an appeals court for a tougher sentence, said attorney Sultan Al-Zahim. Their appeal should include a medical report indicating the injuries inflicted by the father were severe and capable of killing Adel, Al-Zahim said.
The attorney added the mother could apply for custody of Adel and request the court ban the father from visiting his son.