Acquired musculoskeletal dysfunction syndromes (overload syndromes) that cause limitation of the system efficiency belong nowadays to the most serious problems in the medical care of workers. The etiology of overload syndromes is multifactorial, which means that occupational factors constitute only one of many causes fostering the development of those disorders. Occupational factors which increase the risk of musculoskeletal disorders include physical factors related to the work environment or the way the work is performed, such as body posture, value of exerted forces, movement repetitiveness, load handling, mechanical vibration or microclimate as well as psychosocial factors, such as quantitative and qualitative overload, lack of control, lack of social support or work insecurity. The consequence of musculoskeletal overload syndromes is the progressing reduction of its efficiency causing limitation or even loss of work ability, which results in premature exclusion from social and occupational activities. This article presents etiological factors of musculoskeletal complains and overload syndromes and their prevalence in workers.