A biological information measuring instrument comprising a biological sensor section provided on the lower surface of the organism and having a body, a means for securing the body to an arm while directing the lower surface of the body toward the surface side of an organism, a light emitting section for projecting light toward the organism while being in contact with the surface of the organism, and a light receiving section for receiving light emitted from the light emitting section and backscattered from the organism and generating a biological information signal depending on the quantity of received light, and a section provided in the body and operating biological information based on the biological information signal, wherein a light shielding section for preventing light emitted from the light emitting section from impinging directly on the light receiving section is provided between the light emitting section and the light receiving section.
BIOLOGICAL INFORMATION MEASURING INSTRUMENT