A decoupling device includes a lead frame, a capacitor unit, a metal layer, and a high dielectric organic-inorganic composite material layer. The lead frame includes a cathode terminal portion and an anode terminal portion. The capacitor unit is disposed on the lead frame. The capacitor unit includes a cathode portion, an anode portion, and an insulation portion located between the cathode portion and the anode portion. The cathode portion is electrically connected to the cathode terminal portion, and the anode portion is electrically connected to the anode terminal portion. The high dielectric organic-inorganic composite material layer is connected to the capacitor unit in parallel via the metal layer.