采用免疫组化技术和Ｑ５２０图象分析仪对大鼠气道内注入博莱霉素Ａ５后肺内Ⅰ、Ⅲ、Ⅴ型胶原（ＣｏｌⅠ、ＣｏｌⅢ、ＣｏｌⅤ）的动态变化进行了定量分析。结果发现在大鼠肺纤维化病灶中ＣｏｌⅤ的变化与ＣｏｌⅠ、ＣｏｌⅢ不同，其增生出现早，在整个实验周期中呈双峰状曲线，提示在肺纤维化早期和晚期增生的ＣｏｌⅤ具有不同的来源。ＣｏｌⅤ的沉积可能是促使肺纤维化发生、病变长期存在、甚至进行性进展的重要因素。 Immunohistochemistry and Q520 image analyzer were used to quantitatively analyze the dynamic changes of pulmonary collagen type Ⅰ, Ⅲ and type Ⅴ (ColⅠ, Col Ⅲ, ColⅤ) in rats after intratracheal instillation of bleomycin A5. The results showed that the changes of ColⅤ in lung fibrosis lesions were different from that of ColⅠ and Col Ⅲ. The hyperplasia appeared earlier and showed a bimodal curve throughout the experimental period, suggesting that ColⅤ proliferated in early and late stages of pulmonary fibrosis with different sources . Col V deposition may be to promote the occurrence of pulmonary fibrosis, long-term existence of lesions, and even an important factor in the progress.