Disclosed is an organic light emitting display apparatus in which an anode electrode, an organic emission layer, a cathode electrode, and an auxiliary electrode connected to the cathode electrode and disposed on the same layer as that of the anode electrode are disposed in an active area of the substrate, a signal pad and a pad electrode connected to the signal pad and covering a top of the signal pad are disposed in a pad area of the substrate, and a top of the pad electrode has lower oxidation rate than the top of the signal pad.