This study aimed to identify risk and resistance factors associated with the psychological adjustment of fathers of children with obstetrical brachial plexus injuries (OBPI). Participants were 34 fathers of children with OBPI recruited from an Australian OBPI clinic. Measures completed were OBPI severity, disability related stress, family functioning and social support. Together the risk and resistance factors of severity and family functioning accounted for 28% of the total variance in paternal psychological adjustment. Family functioning explained 12% of the variance in psychological adjustment in addition to that explained by severity. These findings highlight the importance of considering paternal perceptions of OBPI severity and family functioning when providing health care to families of children with OBPI.