Thermomyces lanuginosus lipase is one of the most important industrial enzymes.Based on published DNA sequence,the full length cDNA of the lipase was cloned using RT-PCR method.It revealed that the cDNA of the T.lanuginosus lipase gene encoded a protein lipase of 292 amino acid residues.The open reading frame of the cDNA was cloned into the plasmid pET-28b,which was then transformed into E.coil BL21(DE3) strain.The Mr of the expression product was 32 ku by SDS-PAGE.The recombinant E.coli BL21/pET28b-TLL exhibited highest activity of 41 U/mL at 28℃ for 7 h induction with 0.1 mmol/L IPTG after screening of the best medium.