Background:The majority of patients with juvenile idiopathic arthritis (JIA), a prevalent rheumatological condition, are predicted to have abnormal immunoglobulin concentrations upon presentation during the early active disease state, which would normalize after treatment during the inactive disease state. Immunoglobulin concentration can therefore be changed due to Immunomoduler drugs.Objectives:The objective of this study is to investigate the serum levels of IgG, IgM, and IgA in JIA patients in order to better understand the serum immunoglobulin concentration throughout active and inactive disease states.Methods: This is an observational study. The study used to be carried out in the admitted patient’s Department of Paediatrics, Bangabandhu Sheikh Mujib Medical University (BSMMU), Bangladesh from October 2015 to March 2017.The medical records and radiographs of 33 patients who participated in this study were the source of the data. Statistical analysis of the results was previously obtained using window-based software created with Statistical Packages for Social Sciences (SPSS-24).Results: The study comprised 33 JIA patients with ages ranging from 1 to >9 years old. The active states of IgG (g/L), IgM (g/L), and IgA (g/L) in this instance were 13.04±4.41, 3.25±1.80 and 3.29±1.18 respectively, according to Parameter. Additionally, the inactive states of IgG, IgM, and IgA were 9.88±2.31, 1.82±0.88 and 1.34±0.47, respectively. Conclusions:The study concluded that high and abnormal levels of immunoglobulin (IgG, IgM, and IgA) is present among JIA patient in active disease state which became normal in inactive state.