Objective To explore the application conditions of 22 S rule (one of the Westgard rules) in single concentration quali‐ty control .Methods The application scope of 22 S rule was used into the same batch detection of single‐concentration quality control materials .Results The 22 S rule improved the detection rate of system errors .Conclusion 22S rule should be applied to two detec‐tions within a batch when using one quality control material ,as to improve the detection of system error more efficiency .