Abstract: Stem cell preparations and associated products have been widely used in clinical trials and treatment of refractory diseases at home and abroad. Due to the complex preparation process of stem cell preparations, the current microbial examination methods are difficult to meet the relevant needs of safety testing of stem cell preparations, especially the release examination in medical institutions. It is urgent to develop new methods to make stem cell preparations safe and timely for clinical use. This article elaborates on the control process and standards for microbial contaminating in human stem cell preparations, covering raw material selection, preparation processes, release testing, clinical application and sample retention. The aim is to provide a basis for microbial quality control in the clinical application of stem cell preparations.