The invention provides a sponge city rainfall flood diversion and drainage system. The system comprises greening land, water wells and water seepage net pipes, wherein the greening land comprises a planting soil layer, geotechnical cloth, a stone grain layer, a fine sand layer and a foundation body, the fine sand layer is laid at the top of the foundation body, the stone grain layer is laid at thetop of the fine sand layer, the geotechnical cloth is laid at the top of the stone grain layer, the planting soil layer covers the top face of the geotechnical cloth, the water wells are symmetrically formed in the greening land, and the tops of the water wells protrude out of the top surface of the greening land. According to the sponge city rainfall flood diversion and drainage system, rainwater is permeated, guided and drained into the water wells to be stored through uniform distribution of the water seepage net pipes, the water seepage efficiency and the water seepage amount are effectively improved, waste caused by too deep and too wide permeation of the rainwater is avoided, water is kept uniform, meanwhile, the water seepage net pipes are selectively blocked through the arrangement of drainage controllers, excessive loss of bottom layer water in arid weather is effectively avoided, and refined control over the water is achieved.