Transformation of the recombinant plasmid pAT153 containing human cytomegalovirus (HCMV) gene Hind III F fragment into E.coli strain HB 101 was made by the CaCl2 method with a 24% of transformation efficiency. The bacterial colonies containing the recombinant plasmid were selected in colony hybridization with 32P-labelled HCMV Hind III F fragment. The recombinant plasmid was isolated by the modified alkaline lysis method which is characterized by high quality, great quantity, and time-saving. HCMV Hind III F fragment has no homology to the other herpes virus. The 32P-labelled HCMV Hind III F fragment probe could detect 0.25 pg homological sequences of HCMV DNA. The use of this probe allows the detection of HCMV in clinical specimens with the advantages of quickness, good sensitivity and specificity.