The LST-03 lipase from an organic solvent-tolerant Pseudomonas aeruginosa LST-03 has high stability and activity in the presence of various organic solvents. The LST-03 lipase requires a lipase-specific foldase for its activation, and the recombinant LST-03 lipase expressed by a heterogeneous host can be activated using a lipase-specific foldase in vitro. The activity of the activated recombinant LST-03 lipase was further enhanced by addition of calcium ions. This enhancement was suggested to be the result of the conformational transition of the lipase induced by the binding of a calcium ion to the lipase. On the other hand, the organic solvent-stability of the recombinant LST-03 lipase was greatly different from that of the LST-03 lipase prepared from the culture supernatant of a P. aeruginosa LST-03. When the recombinant LST-03 lipase was activated in vitro using the lipase-specific foldase, the foldase was tightly bound to the lipase and influenced the organic solvent-stability of the recombinant lipase.