为探讨常见职业因素在中老年职工工作能力减退中所起的作用。以工作能力指数（ＷＡＩ）为工具，采用成组病例对照研究方法对１８０名工作能力减退的职工（研究组），及８５７名工作能力正常的职工（对照组），进行研究因素危险度的评价。结果显示，工作场所中的一些常见有害因素在研究组的工作环境中更为普遍，经常暴露于粉尘、有害化学物质、噪声、振动、高温、潮湿等环境中的中老年职工发生工作能力减退的危险性增加；在易发生工伤事故的工作环境中工作也是一种有显著意义的因素（ＯＲ＝１７８）。同时较重的体力负荷与中老年职工工作能力减退间有密切联系，反映体力负荷的各项因素都显示出危险度增加，如自觉体力负荷重（ＯＲ＝２５２）、操作重复性（ＯＲ＝１３６）、强迫性劳动姿势（ＯＲ＝１４８）、搬运重物（ＯＲ＝１５９）。相比之下，未发现脑力负荷重会增加工作能力减退的危险。该研究提供的各因素危险度有助于从病因学观点上认识中老年职工健康的有害因素，对进一步采取干预措施改善和增进工作能力具有参考意义 To explore the role of common occupational factors in the diminution of working ability of middle-aged and elderly staff. Using the Work Ability Index (WAI) as a tool, 180 case-control study workers (study group) and 857 workers (control group) with normal working ability were used to evaluate the risk of study factors . The results showed that some common harmful factors in the workplace were more common in the work environment of the research group. The frequent exposure to dust, hazardous chemicals, noise, vibration, high temperature, humidity and other environment, Increased risk; work in a work-prone workplace is also a significant factor (OR = 178). At the same time, the heavy physical workload is closely related to the decline of working ability of middle-aged and old-aged workers. The factors that reflect the physical load all show an increased risk, such as conscious physical load (OR = 2.52), operational repetitiveness = 136), forced labor position (OR = 148), heavy load (OR = 159). In contrast, no significant brain load was found to increase the risk of diminished ability to work. The risk factors provided in this study can help to understand the harmful elements of the health of middle-aged and elderly workers from the perspective of etiology and have reference value for further interventions to improve and enhance their work ability