To provide a finger sack for reading fingerprint with stable fingerprint readability to be used for each individual.

This is a finger sack 77 for reading fingerprint to be applied in a fingerprint reading device 10 in which a fingerprint reading face 44 being an optical member on which fingerprint is placed is irradiated with lights, the lights are fully reflected on the fingerprint reading face 44, and return lights including the picture information of fingerprint are received so that the fingerprint can be optically read. In this case, this finger sack is made of materials having almost the same refractive index as that of the optical member, and this finger sack is mounted on a finger F whose fingerprint should be collected.