Abstract: Based on an eddy permitting, quasi-global oceanic general circulation model, LICOM (LASG/IAP（State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics, Institute of Atmospheric Physics) Climate System Ocean Model), the influences of the horizontal, vertical resolution and advection scheme on the tropical ocean circulation are investigated. Eight sensitivity experiments suggest that (1) higher horizontal resolution results in enhanced currents in the tropical Pacific Ocean, which are closer to the observation than those from experiments with lower horizontal resolution; (2) experiments with finer vertical resolution reveal reasonable vertical structure in the upper tropical ocean; (3) the two-step shape preserving advection scheme makes better simulation of sea surface temperature in the upper ocean, especially in experiments with lower horizontal resolution. However, all experiments show sparser isotherms than the observation, which implies that the physical parameterization of the ocean model still need to be improved, especially of the mixing process.