A tenon groove connecting structure of a front frame and a side panel for a cabinet comprising a front frame and a side panel is disclosed. Wherein, a dovetail groove is formed in an inner edge of the front frame, shoulder grooves are formed in both sides of an opening part of the dovetail groove, and an inner part of the dovetail groove is shaped as inverted trapezoid, and a gap is reserved between at least one side face of the shoulder groove and a corresponding side face of the side panel, and the depth of each shoulder groove accounts for ⅕-½ of the depth of the dovetail groove and the width of the gap is 0.5 -2 mm.