Connor Waugh (21) was last seen at 5pm yesterday (Wednesday) at an address in Stenhousemuir.
Police say Connor has learning difficulties and autism and there is increasing concern for his welfare.
He is described as 6ft4 with copper strawberry blonde hair and was last seen wearing dark blue trousers, a dark blue woolly fleece and black shoes.
Sergeant Anne Begley, of Grangemouth Police Station, said: “We are carrying out a number of enquiries in the Stenhousemuir/Larbert area.
“Due to Connor’s autism and learning difficulties, we would ask people not to approach him if they see him, but to phone the police instead”.
Anyone with any information is asked to contact police on 101 quoting incident reference number 3088 of 21 August