Abstract: Abstract: The air suction type soybean seed-metering device is the core component of the air suction soybean planter. Therefore, the stability and reliability of the machine in working determines the seeding quality of the whole machine. Therefore, high-speed and precision sowing is one of the main development directions of soybeans, corns and other sowing crops. The working state of the seeding machine in the working process is difficult to be directly observed with the naked eye. Once the fault of the metering device occurs, it is very difficult to find and deal with it in time. In?this?paper,?the application of air suction type seed-metering device in high-speed and precision seed metering was discussed, and the seed disc suction performance detection system (SDSPS) was designed. The system used a concave photoelectric sensor to collect the information of seed suction of the platters and used the photoelectric rotary encoder to collect information of the rotation angle of the seed-bearing shaft. By processing the output signal of the photoelectric sensor and the pulse signal of the photoelectric encoder, the seed disc suction performance detection system (SDSPS) can detect every suction holes’ sucking condition, so that the working condition of the whole metering device can be detected. It is of great significance to improve the working performance of air-sucking soybean seed metering device. Bench tests were carried out under six working conditions, and the experimental data were collected. At the same time, the feasibility tests were carried out to detect the absorption of single hole to the seeds. All the test data were collected and compared with the test data of the commonly used system which called Seeding Detecting System based on Image Processing (SDSIP)). Through F-test and t-test (α=0.05), it was found that the total variances of the two systems were the same and the mean values were the same. The results of accuracy analysis showed that the maximum relative error of SDSPS was 0.31% compared with that of SDSIP. The results of system stability analysis showed that the fluctuation amplitude of SDSPS was similar to that of SDSIP, and the maximum relative deviation between SDSPS and SDSIP was less than 1%. The maximum relative error of the SDSPS in the detection of the suction amount of single suction hole was 16.67%. Through the field test，for the effects of SDSPS on the amount of seed lost and the amount of multiple species absorbed, the average relative error of detection value and real value of detection system was 3.87% and 8.42% respectively, and the maximum relative error values were 10.34% and 20.00% respectively. The reason for the error is the complex conditions of the fields, such as the uneven surface environment and so on. The vibration of the machines and tools caused by the rough ground makes the data measured by this method deviate, resulting in abrupt errors. SDSPS can effectively measure the seed absorption performance of seeding suction. There is also a high reliability in the detection of the amount of seed absorbed by a single suction hole. It can provide technical support for the performance detection and improvement of the air suction type seed-metering?device. The test system designed in this paper can effectively detect the working performance of sucking holes in the metering disk. It can also find out the problem of seed suction hole, and provide reference for subsequent improvement and performance improvement of seed tray so as to speed up the research and development of the metering device.