Objective To develop a feasible method for evaluating uncertainty in colony forming units(CFU)on the disinfected skin of nurses of operation room.Methods A nurse of operation room in a hospital involved the study.Ten spots on her disinfected hand skin were selected for evaluation of uncertainty in the acquired data and analysis of reliability of the evaluation methods,according to Technical Norms for Monitoring the Disinfection and Sterilization Quality in Hospitals in Jiangsu Province and JJF1059-1999 Evaluation and Expression of Uncertainty in Measurement.Results The CFU on the disinfected skin of nurse was(4±2)cfu/cm2, which indicated that the disinfection of the nurse's hands was not qualified.Conclusion The evaluation method by our study is reliable for evaluating the uncertainty in CFU on nurse’s disinfected hand skin.It is simple and fitful for the uncertainty evaluation of hospital disinfection effect.