The native collagen with triple helix structure was modified by lauric aldehyde and succinic anhydride, and the biosurfactant retaining native collagen structure was prepared (BCB). The basic surface activity of BCB was investigated and the results showed that the emulsion types of BCB and native collagen were o / w. Compared with native collagen, BCB exhibited better surface activity such as the foam expansion, foam stability, oil absorption capacity, emulsion activity and emulsion stability, but presented lower water absorption capacity. Moreover, the surface tension of BCB decreased with the increased storage time. The wetting power increased with increasing the concentration of BCB.