Aim at problem that it is difficult to monitor sowing quantity for rapeseed drill seed-metering because multiple seeds falling simultaneously, a sowing quantity monitoring device based on linear array CCD sensor was designed. The transmitting terminal of the monitoring device uses a point light source to form a seed monitoring area covered by parallel rays through a set of convex lenses. The receiving end uses a linear array CCD sensor to monitor the rapeseed seed by monitoring the continuous change of pixel values in real time to achieve accurate measurement of the sowing quantity. The indoor test bench was designed for the hole-wheel seedmeter, to carry out the manual single dropping test, seed counting test, continuous sowing quantity monitoring test, and leakage and clogging alarm test. The experimental results show that when the dropping height is less than 150 mm, the monitoring accuracy of the monitoring device for single dropping is 100%. When the metering shaft speed is 20, 30 and 40 r/min, the monitoring accuracy of seed counting for 1 000 seeds is 98.98%, 98.26% and 97.32%, respectively. The monitoring accuracy of continuous sowing quantity of are more than 97% dependent on the sowing time of 5 min,10 min and 20 min.