To provide a polymer which is highly adhesive to an anode and is used for a hole transport layer for an organic electroluminescent element emitting light with high luminance at a low applied voltage; a hole transport layer and an organic electroluminescent element both prepared by using the polymer; and their manufacturing methods.

The organic electroluminescent element showing high luminance at a low applied voltage has a thin hole transport layer excellent in thickness accuracy and surface smoothness and is obtained by bonding the hole transport layer to an amino group-containing coupling agent on the surface of an anode by chemical adsorption, an amide bonding or an imide bonding. The hole transport layer is obtained by using a maleic anhydride polymer which has an N,N-aryl-substituted amino group, such as an N,N-diphenylaminophenyl group or a 9-carbazolyl group, exhibiting hole transport properties and bonded to the molecule.