Provided are an electrophoretic display device and a manufacturing method thereof, and more specifically, electrophoretic e-paper to which a high-k dielectric material is applied in order to improve a reaction rate. The electrophoretic display device of the present invention comprises a plurality of capsules comprising a dielectric fluid and at least one type of particles individually operating in response to an applied electric field and suspended in the dielectric fluid; first and second substrates respectively formed on and below the capsules and having electrodes formed thereon; and a dielectric layer formed on at least one of the first and second substrates to be in contact with the capsules.