Abstract: A non-invasive method to track stem cells implanted is very important for stem cell transplantation in both animal experiments and clinical applications. With high sensitivity and specificity of imaging to many kinds of molecular of cells, nuclear medicine imaging technique should be able to monitor stem cells transplanted in vivo. Basing on presentation of recent developments of radionu-clide imaging and stem cells investigations, possibilities of in vivo tracking of stem cells with various methods are discussed respectively. Receptor imaging may be firstly utilized to solve the problem for its simplicity but with low stability and universality. Screening with SELEX techniques, ap-tamer oligonucleotides specifically targeted to stem cells will be found. Combining antisense imaging with SELEX technique * the problem of tracking stem cells in vivo would be eventually and thoroughly solved.