In this study, we attempted to fabricate dendrimer Langmuir-Blodgett (LB) films functionalized with azobenzene groups in their periphery. It is well known that azoenzene-type compounds undergo an efficient and fully reversible photo-isomerization reaction. We investigated monolayer behaviour and its characteristics at air-water interface by LB method. Then the molecular behaviour shift of the monolayer by 365[nm] light irradiation was also measured because of the isomerization of azobenzene group in periphery. The electrical properties of G4-48Azo dendrimer were compared with between trans form and cis form using metal/dendrimer LB film/metal (MIM) structure and using STM system.