Objective To study the prevalence of transfusion transmitted virus (TTV) in normal children and hepatitis B virus (HBV) carrying children. Methods Anested polymerase chain reaction(nPCR) assay was established using two - set of primers designed from the first open read frame of TTV genome. Serum from the children who received physical examination was tested by nPCR assay for the presence of TTV- DNA. Results The total detectable rate of TTV - DNA in those 230 objects was 17.4% , in which the positive rate of TTV - DNA was 13.7% in normal children and was 25.7% in children carrying HBV. There was significant difference in the positive rate of TTV - DNA between normal children and the children carrying HBV. Conclusion There is TTV infection in normal children,and there is higher positive rate of TTV-DNA in children carrying HBV in Xinjiang.