The invention relates to a sliding door/window locking system. The sliding door/window locking system comprises a bolt base, a bolt sleeve and a bolt rod, wherein the bolt base is arranged on a window frame, and is provided with a first guide groove; the first guide groove is bent to extend; the bolt sleeve is arranged on the side edge of a window leaf, and is provided with a through hole; the bolt rod is slidingly arranged in the through hole, and can move up and down in the vertical direction along the side edge of the window leaf; an adhesive tape is additionally arranged on the window frame; and the bolt rod enters the first guide groove, and extends in the first guide groove to drive the window leaf to move in a direction perpendicular to a plane thereof so as to enable the adhesive tape to bond with the side edge of the window leaf. The sliding door/window locking system enables the window leaf to move in the direction perpendicular to the plane thereof through matching between the bolt rod and the bolt base, so that the adhesive tape is bonded with the side edge of the window leaf, and a sliding door/window is excellent in tightness.