Nowadays, a significant number of people experience low back pain during his lifetime. The causes are not clear at all, but several studies attribute this musculoskeletal disease to economical and psychosocial factors. Among all the treatments proposed, this study focuses in balneotherapy. The search in Medline Database through PubMed, PEDro and Cochrane Library, has yielded some interesting results. Consulted bibliography show that balneotherapy may be effective in the treatment of low back pain, but there are not so many correctly-designed studies to affirm this fact with evidence.