PROBLEM TO BE SOLVED: To provide a brain wave measuring electrode which secures conduction between the electrode and a scalp and does not make the hair get dirty by providing stretchability for absorbing the difference of the shape of the head when measuring brain waves and also having flexibility for easily getting into the hair and reducing pains at a part in contact with the scalp.SOLUTION: A brain measuring electrode 1 has both stretchability and flexibility since it includes: a metal plate 3 a cylindrical member 4 which is erected from the metal plate 3 a metal spring part 2a which is housed so as to be compressed in an axial direction in the cylindrical member 4, and is in contact with the metal plate 3 at a proximal end and a metallic spherical distal end part 2c which is positioned outside the cylindrical member 4, can be brought into contact with a measurement object, and is connected so as to be swung and turned to a free end of the metal spring part 2a through a metal wire part 2b. Thus, when measuring brain waves, the conduction of the electrode and the scalp can be secured while absorbing the difference of the shape of the head without making the hair get dirty.
