The calculation of journal bearing’s performances is taken as an example,and similarities and differences between the modules CFX and Fluent of ANSYS are analyzed using the CFD (computational fluid dynamics) theory. To this end,the calculation models are established and solved using the above modules. And the tribological parameters of the journal bearing are comparatively analyzed at different eccentricity ratios,rotational speeds and the ratios of bearing’s length-diameter. The conclusion reached is that results from two modules have similar overall variation tendency in the bearing performances. However,the maximum pressure and load-carrying capacity by CFX are smaller,while the friction coefficient is greater,compared with those by Fluent. And greater deviations appear at high eccentricity,low rotational speed,or low ratio of bearing’s length-diameter.