Objective: to establish the prevalence, intensity and the risk factors of low back pain in those having nursing as a profession or occupation. This population has important demands for the locomotion system because of the requirements of their job. The muscular-skeletal disorders have been reported as one of the most important causes of working lesions in this profession or occupation. Materials and methods: professional and auxiliary nurses working in two hospitals in Manizales, Colombia who filled out a survey and were asked to undergo anthropometric and functional assessment. Results: In 233 individuals with an average age of 34±10.1, a 67.8% prevalence of low back pain (LBP) was found with values of 75% and 66.8% for men and women respectively. Men and women mobilized patients 11.1±10.8 and 5.5±3.9 times per day respectively. Conclusion: the results of the study demonstrate that low back pain is s frequent disease in the professional and auxiliary nurses in the city of Manizales without any difference in the prevalence regarding gender. In spite of the fact that men perform a higher number of patients' mobilizations per shift, they do not show a greater prevalence of this painful problem.