A bio-signal measuring apparatus, comprising: a finger contact surface configured to be in contact with a finger of a user, wherein the finger contact surface comprises: a first light-transmitting area formed on a first portion of the finger contact surface; at least one second light-transmitting area which is spaced apart from the first light-transmitting area and is formed on a second portion of the finger contact surface; and a non-light-transmitting area formed on a third portion of the finger contact surface other than the first light-transmitting area and the second light-transmitting area; an optical sensor configured to be disposed underneath the finger contact surface and sense a light when the light is reflected from the user, wherein the optical sensor is a pulse wave sensor configured to measure a pulse wave signal from the user when the finger is in contact with the finger contact surface, and wherein the pulse wave sensor comprises: a light source configured to emit the light onto tissue of the finger when the finger is in contact with the finger contact surface through the second light-transmitting area; and a detector configured to detect the light reflected from the tissue of the finger when the finger is in contact with the finger contact surface through the first light-transmitting area; and a texture 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 texture area, so as to allow the user to feel a tactile sensation from the texture area when the finger is in contact with the finger contact surface, wherein the texture area is disposed to allow the user to feel the tactile sensation on both side portions of the finger when the finger is placed in a predetermined direction on the finger contact surface, and the texture area is disposed at the non-light-transmitting area between the first light-transmitting area and the second light-transmitting area. a finger contact surface configured to be in contact with a finger of a user, wherein the finger contact surface comprises: a first light-transmitting area formed on a first portion of the finger contact surface; at least one second light-transmitting area which is spaced apart from the first light-transmitting area and is formed on a second portion of the finger contact surface; and a non-light-transmitting area formed on a third portion of the finger contact surface other than the first light-transmitting area and the second light-transmitting area; a first light-transmitting area formed on a first portion of the finger contact surface; at least one second light-transmitting area which is spaced apart from the first light-transmitting area and is formed on a second portion of the finger contact surface; and a non-light-transmitting area formed on a third portion of the finger contact surface other than the first light-transmitting area and the second light-transmitting area; an optical sensor configured to be disposed underneath the finger contact surface and sense a light when the light is reflected from the user, wherein the optical sensor is a pulse wave sensor configured to measure a pulse wave signal from the user when the finger is in contact with the finger contact surface, and wherein the pulse wave sensor comprises: a light source configured to emit the light onto tissue of the finger when the finger is in contact with the finger contact surface through the second light-transmitting area; and a detector configured to detect the light reflected from the tissue of the finger when the finger is in contact with the finger contact surface through the first light-transmitting area; and a light source configured to emit the light onto tissue of the finger when the finger is in contact with the finger contact surface through the second light-transmitting area; and a detector configured to detect the light reflected from the tissue of the finger when the finger is in contact with the finger contact surface through the first light-transmitting area; and a texture 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 texture area, so as to allow the user to feel a tactile sensation from the texture area when the finger is in contact with the finger contact surface, wherein the texture area is disposed to allow the user to feel the tactile sensation on both side portions of the finger when the finger is placed in a predetermined direction on the finger contact surface, and the texture area is disposed at the non-light-transmitting area between the first light-transmitting area and the second light-transmitting area.