Rainwater flow discarding device

The invention discloses a rainwater flow discarding device. The rainwater flow discarding device comprises a rainwater well, a flow discarding pool and a collecting pool, wherein the flow discarding pool and the collecting pool are communicated with the rainwater well. The rainwater well is communicated with a rainwater collecting pipe network through a first pipeline, the mounting height of a second pipeline used for enabling the collecting pool and the rainwater well to be communicated is larger than that of a third pipeline used for enabling the flow discarding pool and the rainwater well to be communicated, a water pump and a timer electrically connected with the water pump are arranged on the flow discarding pool, and the flow discarding pool is further provided with a rain stopping sensor electrically connected with the timer. Due to the fact that the mounting height of the water inlet pipeline of the flow discarding pool is different form that of the collecting pool, automatic flow discard is achieved, the function that flow discard is not carried out in the situation that rain falls again within 24 hours after rain stops is achieved through the rain stopping sensor and the timer, optimization of rainwater collecting is achieved, and collecting efficiency is improved.