Madura Island and the city of Surabaya, used to be only connected by Ujung-Kamal Port. Later in 2009, Suramadu Bridge began operating. Some people would rather drive over the Suramadu bridge than using the ships so that the amount of ships passanger decreases. This has made PT. ASDP Indonesia Ferry, as the port manager, lose some of the port’s revenue that leads into loss. Along with the free access to pass the Suramadu bridge, it is feared that the amount of ships passanger will continue to decrease. Therefore PT. ASDP Indonesia Ferry requires effort to prevent the greater loss. One of the efforts is to reschedule the ship trips. The ship trips can be affected by the amount of ships passanger. Therefore this research aims to forecast the amount of ships passanger, includes pedestrian, motorbike rider, and car rider. The forecasting is done by the ARIMA Box-Jenkins method. The result shows that ARIMA ([1,12,13], 1,0), ARIMA (0,1,[1,11,12]), and ARIMA (0,1,1) are the best model to forecast the amount of padestrian, motorbike rider, and car rider. The forecast results show that the amount of padestrian passenger is continue to decrease, while the amount of motorbike and car rider are constant.