The design, manufacture and prototype experiment of a new fire-monitor to substitute the traditional bend flow channel with a straight one are presented in this paper in order to cut down the pressure drop when hydraulic fluid goes through it, and the structure with a multi-bar linkage plus a revolute pair is used so as to realize two rotations. The dimensional optimization of four-bar linkage as well as the design of the oscillating mechanism is delivered in sequence; the prototype has also been developed and its performance test has been carried out, finally. The expected results of the work has achieved based on the experimental ends, which has guidance to the redevelopment of novel fire-monitor with longer distance, higher efficiency and lower energy consumption than traditional one.