The moving particle semi-implicit (MIXS) method has demonstrated its usefulness in practical engineering applica-tions. Although it has wide applicability, it is still hard to predict the pressure precisely using the MPS method. A pres-sure-convection particle method based on the MPS method is proposed to overcome this problem. The improved perfor-mance of this new method is validated with computational and measured results. The approach is also applied to compute the problem of sloshing associated with floating body motion in waves. The pressure-convection MPS method demonstrated its capability to improve the prediction of pressure.