We encapsulated marker genes, pRSV-lacZ or pRSV-luc, in immunoliposomes conjugated with antibody targeting laminin B2 in the basal lamina of myotubes. The immunoliposomes mere incubated with matured non-proliferating myotubes differentiated from C2C12 myoblasts. We then evaluated the efficiency of gene transfection by measuring luciferase activity and beta -galactosidase staining. The immunoliposomes conjugated with the antibody specific for myotubes were three times as efficient as control immunoliposomes conjugeted with an antibody not specific for myotubes. However, the efficiency was no more than that by the cationic liposomes without the antibody. These results suggest that laminin B2 is not effective in enhancing the efficiency of gene transfection for non-proliferating myotubes. A specific antibody for surface antigen other than laminin B2 should be chosen in further studies.