摘要:While there are several studies that have investigated the specific relationships between mindfulness, anger rumination, anger-in, and trait anger, no study has investigated all these relationships simultaneously. Therefore, this study examined all relationships between these variables employing a cross-sectional design. Consistent with previous research, we hypothesized that (1) mindfulness will reduce anger rumination, (2) anger rumination will facilitate anger-in and trait anger, and (3) mindfulness will indirectly alleviate anger-in and trait anger through reducing anger rumination. The total of 366 Japanese undergraduates (M = 20.18; SD = 2.27; 51.1% female; 48.9% male) had completed the questionnaires. The results of this study revealed that (1) mindfulness reduced anger rumination, (2) anger rumination facilitated anger-in and trait anger, and (3) mindfulness indirectly alleviated anger-in and trait anger through reducing anger rumination. Although the mediating role of anger rumination was discussed in previous study, it was not based on data. The current study verifies the assumptions by previous study and suggests that anger rumination may be a key factor in treating problems of anger-in and trait anger. We provide new evidence contributing to improved treatment options by specifying the relationships between mindfulness, anger rumination, anger-in, and trait anger.