Taking the pump suction rate of the oil seal as the reliability index,the theoretical contact width,oil side lip angle,air side lip angle,interference,and waist thickness as factors,and the pump suction rate as the response output,the performance of the oil seal was analyzed using orthogonal experimental method.The surface response method was used to fit the limit equation of the pumping rate,and the reliability model of the oil seal pumping rate was established based on the reliability principle.The second order moment method and Monte Carlo method were used to calculate the reliability sensitivity,and the sensitivity of the normal distribution random parameters to the mean value and the standard deviation was analyzed.The results show that the results of the two calculation methods are basically consistent.Based on the sensitivity of the mean value,the theoretical contact width has the greatest influence on reliability,and the oil side lip angle,air side lip angle and interference have positive influence on reliability.Based on the sensitivity of standard deviation,the standard deviation of interference has the greatest influence on reliability,and the standard deviation of all five structural parameters has negative influence on reliability.