A randomized control trial open level and parallel design was conducted in the department of paediatrics, Bangladesh Medical University (BMU). All diagnosed cases of Refractory Polyarticular JIA according to ILAR criteria, unresponsive to MTX were enrolled in this study. After getting written informed consent from the parents/legal guardians, a detailed structured data collection sheet was used for data collection. After enrollment all participants were allocated into experimental group and control group by randomization using random allocation software version 2.0. Total sample size of this study is 50 and 25 participants in each group. All patients of experimental group were given leflunomide along with existing MTX in refractory polyarticular JIA patients and injectable MTX were given at standard dose(15mg/m² BSA) Considering high disease activity steroid were continued in both group at low bridging dose 0.05-1 mg/kg/dose. Patient's disease activity status was assessed by JADAS-27 at initial visit, 6th weeks, 12 weeks and 24 weeks. Functional impairment was assessed by CHAQ-B (DI) at baseline and 24th weeks of treatment. Statistical analysis of the collected data were carried out by using an appropriate statistical tool.