In a pilot study, the masticatory function of patients with juvenile idiopathic arthritis was studied. The chewing efficiency and maximum bite force were measured in five adult patients and compared with a control group consisting of healthy individuals. The chewing efficiency of the patients with juvenile idiopathic arthritis was statistically significantly compromised compared to that of the control group. The maximum bite force was not statistically significantly smaller within this small group. The results of this pilot study support the hypothesis that the masticatory function of patients with juvenile idiopathic arthritis is compromised.We concluded that a more extensive study is necessary to investigate the masticatory function of patients with juvenile idiopathic arthritis and to evaluate the consequences with regard to the quality of life.