A health-sleep model concerning the relationship of mental health and parental rules with time in bed and sleep quality has been developed on the basis of survey data collected from 448 children in the first trimester of the regular school year. The children had a mean age of about 11 years and were attending last two grades of primary school. The relations between mental health characteristics, parental rules concerning sleep, sleep environment, sleep quality and time in bed are analysed using a structural equation model. In addition to a latent variable for ‘mental health’, two uncorrelated latent variables had to be introduced for sleep to achieve a satisfactory fit. One latent variable is related to sleep quality (restorative sleep), and the other relates to lying awake in bed prior to sleep (awake in bed). Restorative sleep shows a strong relationship with mental health, and awake in bed is related to having an own bedroom.