Backgrounds: A body of evidence supports the notion that non-suicidal self-injury individuals exhibit negative bias in social interactions and have difficulties in forgetting negative social feedback. This tendency may induce intense negative emotional responses, thereby increasing self-injury risks. Based on the limited cognitive resources theory, the processing of emotion stimuli by individuals is affected by their cognitive resources capacity and working memory load. It may be possible to prevent individuals from processing unwanted memories by increasing working memory load to deplete the use of remaining cognitive resources and working memory capacity. Methods: Specifically, study 1 explored the characteristics of directed forgetting of social information in individuals with NSSI, and further explore whether working memory load has a positive effect on negative social information directed forgetting in individuals with NSSI. Based on this, study 2 used working memory load training combined with tDCS neuromodulation to form a integrated intervention. Results and Conclusions: The results showed that NSSI individuals have difficulty forgetting negative social information, and working memory load promote directed forgetting of negative social information. Also, the tDCS neuromodulation combined with working memory load training was effective in reducing NSSI, and the effects remained at 1-month follow-up.