The aim of our study is to investigate the factors influencing the quality of life, assessed by the Pediatric Quality of Life Inventory 4.0 (PedsQL4) Generic Score Scales, in Moroccan patients with juvenile idiopathic arthritis. This is a cross-sectional study conducted between January and June 2012, covering children with juvenile idiopathic arthritis (JIA) seen at the consultations of El Ayachi Hospital and Children's Hospital of the University Hospital of Rabat. Quality of life is assessed by the PedsQL4 which is a questionnaire composed of 23 items, completed by the child and the parent; the response to each item ranges from 0 to 100, so that higher scores indicate a better quality of life. The functional impact is assessed by the Childhood Health Assessment Questionnaire (CHAQ), and the disease activity by the number of tender and swollen joints, visual analogue scale (VAS) activity, erythrocyte sedimentation rate (ESR), and C-reactive protein. Forty-seven patients are included; the average age of the patients is 11 ± 3.35 years, and 40.4 % are females, with a median disease duration of 4 (2; 6) years. The oligoarticular form presents 26.7 %, the systemic form 24.4 %, and the enthesic form 22.2 %. The median of PedsQL4 is 80.43 (63.19; 92.93), and the median of the CHAQ is 0 (0; 1). Our study shows that some clinical and biological characteristics have significant effects on PedsQL by both parent and child reports. This study suggests that the achievement of the quality of life of our patients with JIA depends on the disease activity measured by swollen joints, the number of awakenings, parent VAS, physician VAS, patient VAS, and the ESR.