【Objective】To design a sowing performance monitoring system based on photoelectric method, so as to solve the problems of miss-seeding, re-seeding and lack of precision in seeding volume during the single grain precision seeding process for crops such as corns and beans. 【Method】Infrared sensors were applied to capture the pulse signal when the seeds were falling. The signal was processed by a micro-processor, the time gap between successive seed falling was summarized and compared with the designed time gap to obtain the miss-seeding rate, re-seeding rate and seeding volume. Vertical scoop wheel seedmeter was used as the test object to monitor the miss-seeding, re-seeding performance and seeding volume.【Result】The monitoring accuracy rate for single grain of this monitoring system reached 98.8%. Compared with the results of the test-bed for testing performance of the seedmeter, the monitoring error of miss-seeding rate was below 0.3%, the monitoring error of re-seeding rate was below 0.6% and the monitoring accuracy rate of seeding volume was above 94.4%. 【Conclusion】 The monitoring system works stably and has high accuracy.