A suspension mechanism capable of absorbing vibrations in all directions of a Stirling cycle engine 10. The suspension mechanism comprises the Stirling cycle engine 10 including nut members 30 on an outer surface of a casing 28, a holding ring 32 fixed to the nut members 30 substantially coaxially with the Stirling cycle engine 10, a holding cylinder 40 provided so as to cover an outside of the holding ring 32 substantially coaxially therewith; first mounting portions 36 formed in the plural number in one end of an axial direction of the holding ring 32; second mounting portions 38 formed in the same number as that of the first mounting portions 36 in the other end of the axial direction of the holding ring 32; third mounting portions 42 formed in response to the first mounting portions 36 in one end of an axial direction of the holding cylinder 40; fourth mounting portions formed in response to the second mounting portions 38 in the other end of the axial direction of the holding cylinder 40; first extension coil springs 50 suspended between the first mounting portions 36 and the third mounting portions 42; and second extension coil springs 52 suspended between the second mounting portions 38 and the fourth mounting portions 44.