Wayne Parchment, 61, was last seen in the Spital Street area on Thursday, April 10, and police are growing increasingly concerned for his welfare.
He is described as mixed race, around 6ft tall, bald, and with a short grey beard and moustache. Wayne may be wearing black jogging bottoms, a grey top, a dark blue jacket and black shoes.
CCTV from the day he disappeared shows him in Dartford town centre.
Officers say Wayne sometimes becomes confused and may walk with a shuffle. He is likely to be on foot and is known to wear a lanyard around his neck with two keys attached.
He regularly visits areas around Dartford, including Lowfield Street and Princes Road.
Anyone who sees Wayne or knows where he might be should call 999 immediately, quoting reference 12-0856.
