Abstract: A finger clip type oximetry device adaptive to thick and thin fingers comprises a housing, an upper finger pad, a lower finger pad, a light emitting device and a receiver provided and a rotating mechanism. Wall surfaces of the upper and lower finger pads enclose an accommodating cavity. An opening is formed in one end of the accommodating cavity. An arc-shaped first contact surface is provided in an area of the lower finger pad in the accommodating cavity in contact with the pulp of the finger, and an arc-shaped second contact surface is provided in an area of the upper finger pad in the accommodating cavity in contact with the finger back. A first concave surface and second concave surfaces are provided along a transverse direction of the finger. The bending degree of the first concave surface is greater than that of the second concave surfaces.