In this paper, we propose a 3D tactile sensor using self-capacitance measurement for robot. The proposed sensor consists of the two electrodes (E1 and E2) and elastic body. The capacitance between E1 or E2 and GND is measured by switching between E1 and E2. The capacitance between E1 and GND is used to detect the object before contact (proximity range) and to discriminate the material on contact. The capacitance between E2 and GND (E1) is used to detect the indentation on contact. The sensor is attached to the robot surface, and can detect object both before and after contact (3D range). This technique may be applicable to proximity and tactile sensor for robot.