Thomas Murrell, 68, is from Atlanta and traveled to L.A. with his wife to go on a cruise.
His family shared photos of Murrell in the blue shirt, sweat pants and green hat he was wearing when he wandered off.
California Highway Patrol issued a Silver Alert for his disappearance.
Murrell is bald, 6'2", 220 lbs with brown eyes, according to the Silver Alert.
Anyone with information on Murrell's whereabouts is encouraged to call 911.