To allow a patient to have a moderate posture when the patient is lying on his/her back to receive a medical examination on an examination chair.

A mechanism for tilting head and back parts of a patient includes: a geared motor 8 mounted on a headrest arm side 5 of a headrest 1 of the examination chair via a bracket 7; a left-and-right rotary drive support member 9 fixed on a cushion base seat 3 on the cushion side; a rotary axis 10 along the longitudinal direction of the examination chair, fixed at the lower part of the left-and-right rotary drive support member 9; and a rotary axis 8a of the geared motor 8 connected to the rotary axis 10 to form a mechanism for tilting head and back parts of a patient. The head part of the patient is tilted to the side direction by rotating the headrest 1 by rotation of the geared motor 8.