This study examined the mediating role of maladaptive cognition in the relationship of family functioning and internet addiction among adolescent students in Nsukka Urban, Enugu state Nigeria. Four hundred and sixteen (416) adolescents (59.6%, male and40.4% female) who were adolescent students participated in the study. Three hypotheses were tested. Pearson r and HAYES PROCESS macro were used to examine the hypotheses. Results showed that family functioning positively predicted internet addiction as well as maladaptive cognition. Also, maladaptive cognition positively mediated the relationship between family functioning and internet addiction. This study indicated that poor family functioning is a risk factor to internet addiction and that the presence of maladaptive cognition increases the risk associated with it. These findings underscore the importance of examining not only the direct risk factors of internet addiction, but also those factors that when present, can worsen the addiction.