The invention discloses a sludge treatment device for a park artificial lake. The sludge treatment device comprises a dredger body which is provided with a control chamber, a lifting device is connected to the control chamber, and a sledge suction device is connected to the lifting device; the sledge suction device comprises sledge suction frames, sledge suction pipes and sludge conveying pipes; the sledge suction frames comprises the first sledge suction frame and the second sledge suction frame, the first sledge suction frame is internally provided with the sludge conveying pipes, the second sledge suction frame is internally provided with the sledge suction pipes, and a sludge disturbing device is arranged between the sledge suction pipes; and a connection frame is arranged between the first sledge suction frame and the second sledge suction frame and provided with a sucked sledge digging mechanism. A method comprises the steps of 1, construction preparation, 2, dredger selection and sludge conveying pipeline installation, 3, dredger positioning, and 4, lakebed sludge removing through a dredger. The sludge treatment device is simple, easy to achieve, environmentally friendly, free of pollution, low in cost and high in efficiency, and the pollution problem of the artificial lake of a central landscape part is well solved. The method is simple, easy to achieve, scientific, convenient, capable of reducing labor cost, high in working efficiency and wide in application range.