Introduction: The acquaintance of Safety Act Occupational Health must be a duty and a right of employees, to enforce and to protect them from occupational hazards. Objective: The target was to determine the knowledge level of health occupational in working persons of two hospitals in Lima. Methods: Analytical cross-sectional study, surveyed the working health staff in “Jose Casimiro Ulloa National Hospital of Emergency and Olivos Municipal Hospital. It was considerated with good knowledge level who got more than 50% correct answers and socio-labour variables. The results of crude prevalebces reasons (RPc) and tight about the variables socio-educational (RPa) as they are approved. Results: Of the 207 surveys, the 52,9% (109) got an innapropiate know-how. The a50,7% (102) showed that they have received the information about health risk in the work. In the bivariate and multivariate analysis, whom with medical profesion got a greater amount of approved (RPa: 1,87; IC95%: 1,4-3,18) comparison of other professions, adjusted for receiving an entrance examination, training in health at work and information about employment danger. Conclusion: Despite the majority of doctors got a great level of knowledge, the rest of professions didn’t get an adequate acquaintance. This should be taken into account for training and politics generation which could improve the situation.