【Objective】 To investigate the test capability of G6PD for newborn screening laboratories. 【Methods】 According to China National Standard GB/T20470-2006 the requirements for external quality assessment (EQA) in clinical laboratory,2 of lots of G6PD dry blood filter paper for the first time and 5 for the second were sent to 58 and 70 newborn screening laboratories respectively.The feedback information which had been statistically analysed,included: results of G6PD quantitative test (unit:U/gHb),clinical judgment (Positive-negative),resources and information of cut off value.The capability of every laboratory that sent valid information had been evaluated. 【Results】 The valid feedback rate were 86.2% (50/58) and 74.3% (52/70) respectively.Stratified study by reagents indicated that the dispersions of every lot were significant large,for all the 7 lots the CVs (Coefficient of variations) were from 10.67% to 26.77% for that first time but 69.17% to 89.92% for another;robust CVs were from 5.38% to 44.00% and 102.37% to 144.99%.The pass rate of qualitative test were 91.7% and 94.0% respectively which were really much higher than quantitative test whose pass rate were only 53.7% and 74.5%. 【Conclusion】 Because of the large CVs and low pass rate,external quality control program for G6PD are intensively needed in order to improve newborn screening laboratories` test capability and then improve the quality of the population born in China.