Deputies say they have concerns about what they saw at the scene and are investigating it as a suspicious death.
Around 2.30 on Friday afternoon, a neighbor called a relative, trying to reach the resident.
When the man's relative arrived, they discovered his body in his home.
"There's just a lot of questions for us right now. You know normally when you say elderly man you think they died of natural causes. That's not adding up in this situation," said Tony Botti of the Fresno County Sheriff's Office.
Homicide detectives are asking anyone with information or surveillance video of the area to come forward.