STEP data exchanged for collaborative engineering is usually used in CAD systems. However, it is not used so well in PDM systems due to differences in data scope and structure. In order to resolve this inefficiency, we developed the STEP file converter which can manipulate STEP data in web-based PDM systems. The translation scope is limited to AP203. The translator consists of two modules: 1) the viewer which displays STEP data in web environments and 2) mapping editor and translator between STEP schema and PDM database schema.