Abstract: An adjustable button mechanism for a lock includes: a driving tube of a hollow tubular shape, having a first end and a second end, the first end connecting to a driving mechanism of the lock, the second end forming a positioning slot; a connecting member having a first end forming an axial hole and a second end; a protruding member formed at the first end of the connecting member and radially extending into the positioning slot of the driving tube; a button lever placed within the driving tube, and having a first end and a second end, the first end connecting to the driving mechanism, the second end being inserted into the axial hole of the connecting member; and a button placed on the second end of the connecting member, and either the connecting member or the button having an elastically supported lateral member, with the other containing a plurality of holes for selectively receiving the lateral member.