Gavin Smith, 57, who works for 20th Century Fox, was last seen Tuesday night near his home in the community of Oak Park.
"He did not pick up his son Wednesday morning to take him to school, and that is a concern for me," Smith's sister, Tara Addeo, told KABC-TV, Los Angeles. She called her brother a responsible parent who would not simply abandon his family.
The Los Angeles County Sheriff's Department began an investigation late last week and asked the public to be on the lookout for Smith and his white 2000 Mercedes 420E.
The Hollywood Reporter said Smith worked at Fox's office in Calabasas on the northern end of the San Fernando Valley where he managed Fox theaters in Dallas and Oklahoma City. He lived in Oak Park with his family.
There was no word on any domestic problems or indication of foul play in the case, but Smith's wife and co-workers were concerned enough to report him missing.
"We are very concerned about Gavin," Fox Distribution President Chris Aronson told The Hollywood Reporter. "We are actively doing what we can to assist the LA Sheriff's Department."