The link between sleep hygiene and adolescent sleep is well documented, though evidence suggests contributions from other factors, particularly the family environment. The present study examined whether sleep hygiene mediated the relationship between family disorganization and self-reported sleep onset latency, total sleep time, and daytime sleepiness in adolescents. Participants were 217 adolescents, aged 13 to 18 (M = 14.9, SD = 1.0) years, (43% male), recruited from four high schools in South Australia. Sleep hygiene fully mediated the relationship between family disorganization and sleep onset latency (z = 2.77, p < .01) and daytime sleepiness (z = 3.47, p < .01). Only partial mediation was evident for total sleep time (z = 2.50, p < .05). These findings suggest that consideration should be given to the family environment when assessing sleep disturbance in adolescents, and subsequently implementing interventions.