Provided is a multilayer-structured organic electroluminescent diode, and a method of manufacturing a hole transporting layer thereof. The hole transporting layer included in the organic electroluminescent diode is a thin film formed through electrochemical polymerization. The method of manufacturing the hole transporting layer includes the steps of: preparing an electrolyte; electro-polymerizing the electrolyte; controlling thickness of an electropolymerized film; and washing and drying the electropolymerized film as obtained. Specific electropolymerization parameters are set to finely regulate a crosslinking degree and reactivity of the electropolymerized film, thereby solving a prior-art problem that the crosslinking degree and reactivity of a polymer or small molecule hole transporting material in a film state cannot be effectively controlled.