The purpose of this study was to investigate the dimensions of emotional health in two population-based groups (Finland and Canada) of adolescents (ages 13 and 15 years) who self-identify as having a disability or chronic condition, as conceptualized by the WHO International Classification of Functioning, Disability and Health. Data from the 2002 WHO Health Behaviour in School-aged Children survey were used to compare the prevalence of emotional health (items on feeling low, feeling nervous) within and between countries. Eighteen percent of the Canadian and Finnish samples indicated they had a long-time disability, illness or medical condition. Canadian adolescents with disability or chronic conditions felt low significantly more frequently than their classmates without disability or chronic conditions. In both countries, students with disabilities who had more than one functional difficulty were significantly more likely to report feeling low and nervous. These results illustrate that the severity of disability as measured by the number of functional difficulties, and not merely the presence of disability or chronic condition, or particular functional difficulties, may play an important role in the emotional health of adolescents. Health promotion programs may use this information to guide practice to support the emotional health of students with disabilities.