A quality control method using a plurality of analyzers and a control device connected to the analyzers via a network, the method comprising: (a) measuring quality control samples by the analyzers; (b) collecting a plurality of quality control data obtained by measuring the quality control samples; (c) implementing a quality control by the control device based on the collected quality control data; (d) obtaining uncertainty of measurement of analyzer based on uncertainty of analyzer calibration and the quality control data; (e) outputting a result of the quality control; and (f) outputting the uncertainty of measurement is disclosed. A quality control system and an analyzer are also disclosed.