The utility model provides a seeder seed metering operation monitoring device and sowing mechanism, in order to solve the low and not high problem of monitoring precision of current seed metering operation monitoring device monitoring performance, the seeder seed metering operation monitoring device that this application provided should dustproof mechanism contain transparent dust cover, cleaning brush and motor drive part including control processing mechanism, photoelectric sensor and dustproof mechanism, the inboard citadel that forms of transparent dust cover, photoelectric sensor is located this citadel at least, the cleaning brush be located the transparent dust cover the outside and with transparent dust cover outside contact, but cleaning brush and transparent dust cover relative motion, cleaning brush or transparent dust cover are connected with the power take off end of motor drive part. This application has been avoided causing monitoring device's monitoring performance degradation and monitoring the not high problem of precision owing to the pollution of dust to photoelectric sensor when carrying out seed metering the job action through this dustproof mechanism.