This study's goal was to clarify whether psychological capital (PsyCap) mediated the relations between social support and subjective wellbeing among post-secondary students during the COVID-19 pandemic and to assess whether students diagnosed with a learning disability (LD) and/or attention deficit hyperactivity disorder (ADHD) differed from others in their reliance on social support and their level of PsyCap and subjective wellbeing. Participants were 257 students, 152 diagnosed with LD/ADHD and the rest neurotypical. The study used four questionnaires: demographic and academic information; Psychological Capital Questionnaire (PCQ); Subjective Well-Being Index (International Wellbeing Group, International Wellbeing Group, 2006.); social support questionnaire. The results indicated PsyCap mediated relations between social support and subjective wellbeing. Students diagnosed with LD/ADHD differed from neurotypicals in their PsyCap and subjective wellbeing levels, but not in their social support. In addition, the relations between PsyCap and social support were stronger among students diagnosed with LD/ADHD. PsyCap was an important resource for all participants and was related to social support and subjective wellbeing, making it especially valuable for LD/ADHD students facing new and threatening situations, such as the COVID-19 pandemic.