The relation between economically stressful factors and musculoskeletal disorders was investigated by comparing two school lunch service centres (A and B). The Action Limit advocated by NIOSH was used to evaluate the manual lifting tasks. The workers in centre A had a significantly higher prevalence of musculoskeletal complaints, more clinical findings and greater medical treatment experience than those in centre B. The ratio of the actual lifting load to the Action Limit was also larger in centre A than in centre B. The ergonomic advantages in centre B, which resulted in markedly decreased repetitive use of arms and hands, improvement of working postures, lower frequencies and shorter travel distance in liftings, seemed to be related to this difference. The main factors provoking the excess of musculoskeletal disorders in school lunch service were revealed, and the necessity for and the possibility of providing improved working conditions were also indicated.