To provide a transfer supporting device capable of avoiding interference with a care receiver by a completely new idea.

The transfer supporting device 100 includes: a trolley 1; an arm portion 2 that is pivotably attached to the trolley 1; a body holder 3 provided on the arm portion 2 to hold a care receiver M; a third motor 15 as a driving source that pivots the arm portion 2; and a driving force transmission mechanism D. The driving force transmission mechanism D transmits the driving force of the third motor 15 to the body holder 3 while the care receiver M is being transferred, and does not substantially transmit the driving force of the third motor 15 to the body holder 3 while the care receiver M is not being transferred.