Abstract: The hydraulic system is an important component of agricultural machinery and the fundamental guarantee for the normal operation of agricultural machinery. However, its long-term operation in harsh environments and improper maintenance result in a relatively high failure rate. This article mainly discusses common faults and maintenance measures of agricultural machinery hydraulic system. Explain the characteristics and diagnostic requirements of hydraulic system faults in agricultural machinery, analyze the common causes of hydraulic system faults and corresponding strategies, and propose targeted maintenance measures for related problems.