According to the sentence, the accused was "in a state of maximum irritation" as his son hadn't done his maths homework in a day and a half.
"He smacked him over the head, grabbed him by the arm, lifted him up from the chair he was sitting on, threw him on the bed and spanked him several times on his backside", the court heard.
As a result of his actions, the young boy suffered bruising to his arm and lip.
The only witness was the victim’s five-year-old sister, local online daily Noticias de Navarra reported on Monday.
The man will have to pay €213,22 ($323) to his son for the physical injuries he sustained.
He was also given a six-month restraining order and 56 days of community service.
The magistrate told the court that the man's disciplinary measures as a father were "flagrantly excessive".