BackgroundYoung people have been especially affected by the psychosocial consequences of the covid-19 pandemic. Covid-19 has potentially also been more stressful for vulnerable groups with mental health problems.MethodsIn this cross-sectional study, the psychosocial effects of covid-19 in a vulnerable group of adolescents with nonsuicidal self-injury (NSSI) from a sample of 1602 Swedish high-school students were examined. Data were collected in 2020 and 2021. First, adolescents with and without NSSI were compared on how they perceived the psychosocial impact of covid-19, and second, a hierarchical multiple regression analysis was used to examine whether lifetime NSSI experience was associated with perceived psychosocial consequences of covid-19, when demographic variables and symptoms of mental health problems were controlled for. Interaction effects were also examined.ResultsSignificantly more individuals with NSSI reported being burdened by covid-19 compared to those without NSSI. When demographic variables and mental health symptoms were controlled for, adding NSSI experience did not, however, increase the amount of variance explained in the model. The total model explained 23.2% of the variance in perceived psychosocial impact of covid-19. Perceiving the family’s financial situation as poor and neither good nor bad, studying a theoretical high school program, symptoms of depression and difficulties with emotion regulation were significantly associated with perceived negative psychosocial impact of the covid-19 pandemic. There was a significant interaction effect between NSSI experience and depressive symptoms. The effect of NSSI experience was larger when depressive symptoms were lower.ConclusionsLifetime NSSI experience in itself was not associated with psychosocial covid-19 consequences when other variables were controlled for, whereas symptoms of depression and difficulties with emotion regulation were. Results imply that vulnerable adolescents with mental health symptoms need special attention and access to mental health support in order to prevent further stress and worsening of mental health symptoms in the wake of the covid-19 pandemic.