The invention discloses a control method for one-key discharging of precipitation grooves in polymerization production. According to the control method, particularly, the loop operation from flushingto discharging and the artificial judgement operation, both of which are conducted in the discharging process of the precipitation groove A / the precipitation groove B frequently, are changed to be completed under DCS automatic control; a discharging starting button, a discharging stopping button, a manual operation button, an automatic operation button, a pause button and other relative programsare preset at a central control operation station, the selection between a steam-lifting feeding pump and a backup pump is preset, a discharging check valve and a monomer recycling check valve of theprecipitation groove A / the precipitation groove B are additionally arranged, and the liquid level value, the pressure value and the cleaning time are preset; when the preset logic requirements of adischarging program and a flushing program are met, the next program is automatically initiated, and meanwhile, switching between a manual operation mode and an automatic operation mode can be achieved according to production demands; the program can be initiated or paused or stopped in real time by pushing one button, and after all the programs are completed, the positions of all internal switches and pump valves are reset to initial states; by adopting the control method, operation can reach an ideal control standard better, and meanwhile, the control method has the advantages that operation is convenient and fast, influences caused by human factors are overcome, and optimization and precision control of crucial processes during discharging of the precipitation grooves can be achieved.