Abstract: [Objectives] Intended to analyze the influence of interceptors on the resistance and motion characteristics of ships in regular waves. [Methods] Taking a semi-displacement ship as the research object, the numerical simulation of the resistance and motion characteristics of the ship with and without interceptor in regular waves was carried out based on RANS method and overset mesh. The variation laws of ship resistance, attitude and motion response with wavelength and ship speed were summarized. [Results] The results show that the resistance reduction effect of interceptor in regular wave was about 1% - 2.5% higher than that in calm water. The influence of interceptor on the heave and pitch transfer functions increases with the increase of the wavelength. The average reduction rates of heave transfer function TF3 and pitch transfer function TF5 under λ = 2LPP condition were 3.5% and 1.4%. When the phenomenon of green water on deck occurs, the interceptor can reduce the TF3 and TF5 by 9% and 3%. [Conclusions] The research methods and achievements can provide technical references for the design and performance prediction of ship energy-saving devices.