An electrostatic separator is obtained that can improve the efficiency of separating material fragments contained in a mixture. The electrostatic separator includes a transfer unit (130) and a counter electrode (180). The transfer unit (130) transfers a mixture (100) electrically charged, which is a target fed into an electrostatic field space to be separated according to a state of electrical charging. The transfer unit (130) includes an end portion (1) in a direction of transfer of the mixture (100). The counter electrode (180) faces the end portion (1). The counter electrode (180) can form an electric field between the end portion (1) and the counter electrode (180) upon application of a voltage. A first surface portion of the counter electrode (180) facing the end portion (1) has an area larger than an area of a second surface portion of the end portion (1) facing the counter electrode (180) and functioning as an electrode.