Work-related musculoskeletal disorders (WMSDs) have become the most common occupational diseases in the international workplace today. Among all occupational diseases, expenses are highest for WMSDs. It is known that poor ergonomic design in the workplace is an important cause of WMSDs, but studies of ergonomic factors in WMSDs in the workplace have been relatively scarce. It is generally agreed that the risk factors of WMSDs are over-exertion, high repetition, prolonged exposure, cold and vibration, and awkward posture. Among these five factors, four of them are not easy to alter except awkward posture. This posture may bring aches to the neck, shoulder, waist, wrist and other joints, or lead to tiredness and illness. To eliminate these aches, tiredness and illness, we can use ergonomics techniques to improve the installations and conditions in workplace so that laborers can work in a most natural and effortless posture. This study uses the techniques of ergonomical intervention to improve the bad posture in workplace and depending on Key Indicators Method (KIM) to check the benefit before and after the intervention. The risk of ingredients weighing is by level 3 become level 2. In general, The risk of case is significantly improved and eliminate the WMDS in workplace. KIM is a specific checklist and could be easily used in most operation such as lifting, holding, transporting and pushing-pulling etc. The estimation of KIM can be very brief, so it is appropriate to diagnose workplace in a short time.