A bio-signal measuring apparatus may include: a finger contact surface configured to be in contact with a finger of a user; an optical sensor configured to be disposed underneath the finger contact surface and sense a light when the light is reflected from the user, and a textured area formed on the finger contact surface at a boundary of the optical sensor, and configured to provide a texture different from a texture of a remaining area of the finger contact surface other than the textured area, so as to allow the user to feel a tactile sensation from the textured area when the finger is in contact with the finger contact surface.