The invention relates to the field of dust prevention of low-voltage switch cabinets, in particular to a built-in dust prevention structure suitable for a low-voltage switch cabinet, which comprises a main body, a dustproof mechanism, an opening and closing mechanism, a lifting mechanism, a folding mechanism and an auxiliary mechanism, and through the arrangement of the dustproof mechanism, a dust filtering effect can be achieved while the main body is cooled, a dustproof component can be detached and cleaned without opening the main body, normal operation of the main body is guaranteed, through the arrangement of the auxiliary mechanism, the dustproof component is conveniently detached and replaced, the use effect of the main body is improved, and the practicability is high. By arranging the lifting mechanism, a moving part can extend to the bottom end of the main body, so that the main body can be conveniently moved in a labor-saving manner, by arranging the folding mechanism, the moving part in the lifting mechanism can be conveniently rotated, the occupied space is reduced through the design of a folding crank, and the usable space of the main body is increased; and the folding mechanism is convenient to unfold through the arrangement of the opening and closing mechanism, the folding mechanism can be prevented from being exposed to the outside, and the attractiveness of the main body is improved.