Background: Camouflaging, defined as the use of strategies to compensate for or hide autistic traits, is associated with internalizing behaviour (i.e., anxiety and depression) in both autistic and non-autistic people. Non-autistic adults who have poorer social competence tend to engage in more camouflaging, thus it’s unclear whether the increase in internalizing behaviour associated with camouflaging may be explained by poor social competence, rather than camouflaging itself. The purpose of this study was to extend previous research on camouflaging and internalizing behaviour among non-autistic people through examination of the role of social competence. Methods: In this study, 315 non-autistic young adults completed the Multidimensional Social Competence Scale (MSCS) to assess their social competence, the Camouflaging of Autistic Traits Questionnaire (CAT-Q) to assess their use of camouflaging strategies, and the Behaviour Assessment Scale for Children 2 – Self-Report of Personality, College Version (BASC-2 SRP-COL) to assess their internalizing behaviour. Results: We found that camouflaging predicted internalizing behaviour among non-autistic young adults after controlling for social competence, autistic traits, age, IQ, and gender. Camouflaging partially mediated the relationship between social competence and internalizing behaviours. Conclusions: These results suggest that the use of camouflaging strategies is uniquely associated with internalizing behaviour over and above social competence and may, in part, contribute to the increased internalizing behaviours observed in individuals with poorer social competence.