Using the internationally popular OPTIMOOR software for ship mooring analysis,systematic analysis of ship mooring stability subjected to long-period waves is carried out.The influence of period,wave height and incident angle on ship mooring stability are studied.Through the analysis of the calculation results,the influence of wave height and incident angle on the ship’s heave motion is very obvious,and the period has the most obvious influence on the ship’s surge motion.At the same time,the maximum mooring line tension and three factors of long-period wave(including wave period,wave height and incident angle)show a positive correlation in a certain value interval,and with the increase of wave factors,the mooring line tension distribution shows obvious unevenness.Moreover,maximum fender reaction and long-period wave also show a positive correlation in a certain value interval.For the two wave factors of period and incident angle,the larger the value are,the more balanced the four groups of fender reaction will be.