Abstract: In order to accurately control the volume and range of lubricant injection in manual operation, the nozzle was modified on the basis of ultrasonic atomization technology and focusing tube principle, and a precise lubrication system for the bottom chains in the tobacco silo was designed. The working parameter optimization of oil circuit and air circuit indicated that the oil injection was more effective when the single oil pumping volume of peristaltic pump was 0.4 mL and the compressed air pressure was 0.15-0.25 MPa. The designed lubrication system was tested on a silo supplied by Kunming Marine Equipment Group Limited Corporation, the results showed that the consumption of lubricating oil reduced by 47.5% on average, the manual operation time decreased by 86.8% averagely, and the lubrication cycle prolonged from 3 to 6 months, and the fine atomization and accurate injection of lubricating oil were realized. This technology provides supports for promoting the lubrication efficiency of bottom chains in tobacco silo and reducing the material consumption in production.