The invention discloses a novel rain gauge, and belongs to the technical field of rainwater treatment device. The rain gauge includes a rain gauge outer cover; a water collection hopper and a water collection pipe are fixedly connected inside the rain gauge outer cover; the upper side of the water collection hopper is fixedly connected with rainwater sensors; the lower side of the water collection pipe is connected with a solenoid valve; the solenoid valve can be opened or closed under the function of the rainwater sensor; a float switch is connected inside the water collection pipe; and a signal line is fixedly connected on the rain gauge outer cover to be connected with a control box. The novel rain gauge provided by the invention is simple in structure and convenient to install and use, ca effectively control the flow discarding quantity of rainwater according to fresh rainfall, and can realize control of a lifting type closure rubber flap check valve or lifting type flexible flap valve of a flow discarding well through a PLC, and by use of the rain gauge, the degree of automation of the flow discarding well can be improved.