A garment steamer comprises a steamer body, a supporting piece and an ironing board, wherein one end of the supporting piece is connected with the steamer body, and the other end of the supporting piece is connected with the ironing board. The garment steamer is characterized in that a screw rotary knob is connected with the top end of the supporting piece and the bottom of the middle section of the ironing board in a limited mode, and the ironing board can rotate vertically or transversely relative to the supporting piece and can be positioned to the required angle. Compared with the prior art, the garment steamer has the advantages that the ironing board can be adjusted to any position between the horizontal plane and the vertical plane, and the garment steamer is simple and reasonable in structure and convenient to operate.