Introduction & Objective: Occupational injuries are still one of the main reasons of disability among industrial workers. According to surveys, more than 15 million accidents happen daily all over the world. The magnitude of the problem is well known in most developed countries but in developing countries less attention has been paid to this growing public health problem. Materials & Methods: This cross sectional study was conducted between 2002 – 2005 in three hospitals in Tehran - Iran. The process of data collection was conducted by using check lists and questionnaires. Results: The results have shown that adult group age between16 to 25 comprised 43% of patients and 78% of patients were under 35 years old. The most reason of accidents was insufficient safety of machines (42%). Forty-five percent of accidents were happened in morning shift .The majority of injuries occurred in summer. There was no difference between experienced workers and simple workers. Press machines and metal casters were the first line of making danger (25%). There was no significant difference between left dominant or right dominate hand patients in the side of trauma injury. Conclusions: These results show the need to implement prevention programs in industry sectors to reduce the prevalence of upper extremity injury. Another important point is the major role of safety educations for worker before employment.