Vertical type organic light emitting transistors (OLETs) using C-60 as a n-type active material and MEH-PPV as an emitting polymer were fabricated. C-60 shows n-type semiconductor property and relatively high electron mobility. Furthermore, MEH-PPV has high quantum efficiency for light emitting diode. We have investigated structural effects of C-60 and Bphen blocking layer on the performance of light emitting diode consisting of ITO/PEDOT-PSS (50 nm)/MEH-PPV (80 nm)/Bphen (3 nm)/C-60 (30 nm)/Al (100 nm). Vertical type OLET has layered structure of metal(source)/C-60/metal(gate)/C-60/Bphen/MEH-PPV/PEDOT-PSS/ITO glass. The thickness of source and gate electrode was 100 nm and 10 nm, respectively. Source and gate electrodes were deposited with several kinds of materials. The characteristics of the fabricated OLETs were studied from the measurements of current-voltage and on-off ratio.