Court records show 58-year-old Mark O. Porter entered the plea Wednesday to a federal housing violation charge and was taken into custody ahead of a detention hearing.
Prosecutors say he yelled a racial slur at the 7-year-old boy and told him to "get out of here" in Draper on Nov. 3.
Charges say Porter hit the father in the neck with a stun cane when he told Porter not to yell at his son.
Porter faces up to 10 years in prison.
Attorney Gabriel White said Thursday he no longer represents Porter but maintains his innocence.