Abstract： Objective To assess the value of CMV viral load test in the diagnosis and prognostic judgment of infantile cytomegalovirus infection with whole blood and urine specimens. Methods 50 infants with active CMV infection were selected, which pp65 antigen was positive in serological detection and either CMV-IgM positive or the titer of CMV-IgG ≥40. The viral load in whole blood and urine specimens was detected before and after a course of preemptive ganciclovir treatment and the pp65 antigen was determined after treatment. Results 98% patients were manifested as cytomegalovirus viral load quantitative measurement in whole blood positive before the treatment, while 14% after. The positive ratio of pp65 assay after therapy was 6%. And there was no significant difference between the results of the two kinds of detection methods measurement in urine before and after treatment was 98% and 90%, respectively. The results of urinary viral load quantitative detection did not coincide with clinical characteristics of CMV infection (P＜0.05,Sp＝0.11,PVP＝0.55, (Youden's index)＝0.09). Conclusions Good coincidence could be found between CMV-DNA quantitative measurement in whole blood and pp65 antigenemia assay. And the former could be used as a diagnostic index of CMV positive infection. While single urinary viral load quantitative detection had no significance for the distinction between active and latent CMV infection and dynamic monitoring of CMV treatment.