When getting the results of clinical diagnosis, before concluding it is normal or abnormal, we must refer the reference intervals. There are no reference intervals for the Vietnamese, therefore, the clinical laboratories are using the reference intervals from many different sources, so the conclusion can be different, it can make the physicians give treating decision differently. In this study, the authors survey and collect the reference intervals of biochemistry, immunology using at the clinical laboratories to evaluate the same (the difference) of each parameter reference interval between laboratories, so that the scientists, the policymakers have essential informations to do other studies, or to set up policies, that make the conclusions in clinical diagnosis be more reliable and help the physicians give the right decisions.