The steering system noise is one of the main noise sources in submarine stealth condition. Combined with the composition of the steering system, the noise source of each component is sorted out systematically, and corresponding vibration and noise reduction design measures are proposed. As the main noise source of the steering system, emphasis is placed on analyzing the noise mechanism of the rudder hydraulic system, which is divided into two categories and six types according to steady state and transient operating conditions. Finally, it is pointed out that the new type electro-hydraulic steering gear, based on direct drive servo control principle, is the future development trend.