Although stem cells are commonly isolated by fluorescence-activated cell sorting or magnetic affinity cell sorting, they are very expensive, and they need known markers. However, there is no specific marker for liver stem/progenitor cells (LSPCs). Here, we describe a convenient and efficient method (three-step method) to enrich LSPCs. The fetal liver cells (FLCs) were firstly enriched by Percoll discontinuous gradient centrifugation from the rat fetal liver. Then the FLCs in culture were purified to be homogeneous in size by differential trypsinization and differential adherence. Finally, fetal liver stem/progenitor cells (FLSPCs) were enriched from purified FLCs by Percoll continuous gradient centrifugation. Flow cytometric analysis combining with marker CD133 was used to detect the purity of FLSPCs and evaluate the isolating effects of the three-step method.