A support member for a wearable instrument which is mounted on a user's head part in cooperation with an eyeglass frame includes a head-contact portion that comes in contact with the user's head part, a temple-contact portion that comes in contact with a temple part of the eyeglass frame on a surface opposite of the head-contact portion, an instrument-connection portion for a wearable instrument that is disposed on the side of the temple-contact portion. Here, the temple-contact portion 30 has a first contact surface that comes in contact with a head-side surface of the temple part.