Vapor-deposited films of poly(N-vinylcarbazole) (PVCz) were used as hole transport layers in organic electroluminescent devices. Hole transporting ability of the vapor-deposited PVCz films in the double-layered cell remarkably depended on their film morphology. Light emission was obtained only when a thin, homogeneous PVCz film(10-15 nm in thickness) was deposited on an anode substrate which was kept st 100 degrees C during deposition. When the PVCz film was overcoated on a low molecular hole transporting layer, the EL performance of the mutilayered device was retained for a longer time as compared with that without the PVCz deposition. This improved durability was ascribed to the PVCz layer which prevents the low molecular layer from being degraded by aggregation.