Objective To understand the factors which would effect the quality of blood specimen,and then set the countermeasures. Methods Investigated the whole course of venous blood sampling by the quality control group,and then analyzed the data. Results 13% nursing personnel did not know the factors which would effect the quality of blood specimen.9% nursing personnel collect venous blood with a nonstandard way.The factors which would effect the quality of blood specimen were: test tube was not enough dry,the injector air leak,mechanical injury,the time of deliver specimen was too long,anticoagulant clotting,and so on. Conclusion Strengthen the training of professional skill and knowledge for nursing personnel,and then improve the quality of blood specimen.