When the sliding bearing rotates at high speed,the lubricating oil will inevitably produce bubbles.Due to the limitation of the machining accuracy of the sliding bearing,the existence of roundness error is also inevitable.Therefore,it is necessary to comprehensively consider the influence of cavitation and roundness error on the static lubrication characteristics of sliding bearing.The coupled Reynolds equation considering the influence of the roundness error and cavitation was obtained by combining the equations considering the roundness error of journal and bush and the variation of cavitation viscosity and density.The influence of cavitation and roundness error on the static characteristic parameters of journal bearing was analyzed by iteratively solving Reynolds equation.The results show that the influence of roundness error on maximum oil film pressure and bearing capacity is greater than that of cavitation,and the influence of cavitation on end discharge is greater than that of roundness error.The influence of roundness error on friction power consumption is greater than that of cavitation when eccentricity is small,and the influence of cavitation on friction power consumption is greater than that of roundness error when eccentricity is large.Cavitation increases the maximum film pressure,end discharge,bearing capacity and friction power consumption.The roundness error has a great influence on the oil film pressure,bearing capacity and friction power consumption,but has less influence on the end discharge.