Introduction:According to SOSORT, conservative treatment of idiopathic scoliosis (IS) includes physiotherapy and bracing. The main goal of treatment is to prevent of progression of the curvature as well as improvement the appearance. The aim of the study is to present the results of conservative treatment of girls aged 12 years with progressive idiopathic scoliosis. A case study: The first diagnostic was performed in March 2010 due to asymmetry of scapulas observed by the mother. The girl was referred to an orthopedist for a more detailed diagnostics. The radiographic assessment found: the right-sided curvature in the thoracic (Th6-Th11, 30°) and left-sided in the thoraco-lumbar (Th11-L4, 30°). The Risser sign was determined (0). It was recommended Cheneau brace (23 hours per day) as well as intensive physiotherapy. In the conversation with parents and girl, it was established that they failed to comply the recommendation. The control radiographic exam (September, 2010) revealed the progression of the right thoracic curve (Th6-Th11, 36°). It was recommended more systematic wearing the brace and exercises. The X-ray performed in June 2011 showed decrease of the Cobb angle (Th6-Th11, 18° right and Th11-L4, 14° left). Risser sign value was (1). The menarche occurred in November 2011. The patient continued the treatment with the brace and physiotherapy. In September 2013 performed the control X-ray exam (Th5- Th11, 15°, Th11-L4, 11°). The Risser sign was determined (4).The physician decided by the end of treatment with Chenenau brace and recommended the continuation of physiotherapy to improve the appearance. Summary and conclusion: The conservative treatment (Cheneau brace and physiotherapy) can lead to decrease the Cobb angle in children with IS.