To easily execute, on a lock attaching site, creation of an environment equivalent to a butt end of a door on the inner wall surface side of the door similarly to the case of fitting a dug-in lock to the butt end.

The surface attached lock unit includes at least: a case-like storage body 7A fixed to an inner wall surface 1a of a door 1 in a surface attached state through first fixing means 17; a lock 8A fixedly stored in the case-like storage body through second fixing means 25; an attaching body 9A provided on an outer wall surface 7b of the case-like storage body and provided with a pair of projection piece parts 9b; and a cover pedestal 10A provided with a vertically long internal space 31 larger than the case-like storage body 7A, and also fixed to the attaching body 9A through third fixing means 29 in the state of wholly covering the attaching body 9A and the case-like storage body 7A.