Scratches on hydrodynamic bearings are one of leading causes of bearing deterioration and reduced bearing life. Although many empirical studies have examined this issue, there are relatively few numerical modeling researches. In this study, a hydrothermodynamic numerical simulation model was employed to gain a better understanding of the impact of scratches on the two main working factors in hydrodynamic journal bearings: Pressure and temperature distribution. Three parameters were used to categorize the scratches: Depth, width, and location. The results demonstrate that, all three parameters have different degrees of influence on the pressure and temperature distribution within the bearing. Specifically, the depth of the scratches was found to have a significant influence, particularly when they exceeded the bearing clearance. The width of the scratches was more noticeable when they were wider, while the location of the scratches was found to have no significant influence.