Human lactoferrin (hLf) is a multifunctional iron-binding glycoprotein. In this study, we amplified hLf cDNA by reverse transcription-polymerase chain reaction from normal human mammary gland. The nucleotide sequence of the hLf was identical to the known hLf. We constructed a recombinant virus, vBm-hLf, harboring the hLf gene and exploited the BmN cells as host to produce recombinant human lactoferrin (rhLf). It was found that a recombinant protein with a molecular mass of approximately 78 kDa was expressed. Approximately 13.5 microg rhLf was purified from 1-2x10(5) BmN cells infected by vBm-hLf and the rhLf proved to be biologically active. This method established in our study will pave the way for efficient production of rhLf for further application of this protein in the future.