We aimed to investigate the Health Related Quality of Life and related clinical variables (HRQoL) of children with Autism Spectrum Disorders (ASD). We included 102 children with ASD (46 with autism, 38 with pervasive developmental disorder not otherwise specified (PDD-NOS) and 18 with Asperger's syndrome (AS)) and 39 typically developing children as a control (TDC), between 3 and 18 years of age. The mothers scored the Pediatric Quality of Life Inventory 4.0 (PedsQLTM 4.0). The physical health, psychosocial health and total summary score of ASD group were significantly lower than TDC. Within ASD group, psychosocial (p less than 0.001), social, school functioning and total summary score (p less than 0.001) of the autism group were lower than AS, and PDD-NOS. The scores of AS and PDD-NOS were similar. PedsQL scores differed between the groups who take psychotropic medication and continue to special and formal education in ASD. PedsQL scores were negatively correlated with the Childhood Autism Rating Scale (CARS) score and positively correlated with the age that first signs appeared (p less than 0.01). Within ASD group the children with autism had the poorer HRQoL than AS and PDD-NOS. The correlation between HRQoL and CARS scores was moderate. The severity of ASD has negative effects on HRQoL. (Contains 4 tables.)