This study aimed to find a simple and effective mindfulness training method for intervening depression. 95 university students with moderate or severe depression participated in the study and they were divided into three mindfulness training groups: 8-week complete group, 8-week informal group, and 4-week group. All subjects completed Beck Depression Inventory (BDI-Ⅱ) and Five Fact Mindfulness Questionnaire (FFMQ) before the intervention, after which, 55 subjects completed the assessments once more. Results showed the scores of specific dimensions representing mindfulness levels were different. For the 4-week group, scores of description, action aware and nonjudge significantly were improved, while the other two groups were improved significantly on all the five dimensions, especially the informal training group. In the discussion, it focused more on the effects of training time and training contents, and briefly discussed the relation of subjects dropout, subjects attendance, homework completion status and intervention effects. In conclusion, all the three intervention modes have magnificent intervention effects. Integrated many sided, 8-week informal training is of the best effects, which may be considered as a better mindfulness training mode henceforth, however, the comparison between the formal training and informal training still needs further study.