A bearing device configured to support a rotary member to a fixed member via a rolling bearing (31a, 31b) and comprising a compressed gas injection nozzle configured to inject compressed gas into a gap (g) between the rotary member and the fixed member in the vicinity of the rolling bearing (31a, 31b), characterized by a displacement measuring unit configured to measure a radial direction displacement of the rotary member by using the compressed gas supplied into the gap (g) to be measured, the displacement measuring unit including a plurality of pairs of a displacement detecting unit and a pressure loss measuring unit, and an arithmetic processing unit, the plurality of pairs of the displacement detecting unit and the pressure loss measuring unit being arranged in a circumferential direction, the displacement detecting unit having the compressed gas injection nozzle, the pressure loss measuring unit being configured to measure a pressure loss of the compressed gas supplied to the displacement detecting unit, the arithmetic processing unit being configured to calculate the radial direction displacement by converting the measured pressure loss to the radial direction displacement, wherein each of the displacement detecting units has a gas recovery groove (81a, 81b) configured to recover the compressed gas injected into the gap (g) to be measured from the compressed gas injection nozzle, the gas recovery groove (81a, 81b) being formed on one side or both sides with respect to an axis of the compressed gas injection nozzle, and the arithmetic processing unit is configured to calculate a load exerted on the rotary member based on measurement results of the pressure loss measuring units. a displacement measuring unit configured to measure a radial direction displacement of the rotary member by using the compressed gas supplied into the gap (g) to be measured, the displacement measuring unit including a plurality of pairs of a displacement detecting unit and a pressure loss measuring unit, and an arithmetic processing unit, the plurality of pairs of the displacement detecting unit and the pressure loss measuring unit being arranged in a circumferential direction, the displacement detecting unit having the compressed gas injection nozzle, the pressure loss measuring unit being configured to measure a pressure loss of the compressed gas supplied to the displacement detecting unit, the arithmetic processing unit being configured to calculate the radial direction displacement by converting the measured pressure loss to the radial direction displacement, wherein the plurality of pairs of the displacement detecting unit and the pressure loss measuring unit being arranged in a circumferential direction, the displacement detecting unit having the compressed gas injection nozzle, the pressure loss measuring unit being configured to measure a pressure loss of the compressed gas supplied to the displacement detecting unit, the arithmetic processing unit being configured to calculate the radial direction displacement by converting the measured pressure loss to the radial direction displacement, wherein each of the displacement detecting units has a gas recovery groove (81a, 81b) configured to recover the compressed gas injected into the gap (g) to be measured from the compressed gas injection nozzle, the gas recovery groove (81a, 81b) being formed on one side or both sides with respect to an axis of the compressed gas injection nozzle, and the arithmetic processing unit is configured to calculate a load exerted on the rotary member based on measurement results of the pressure loss measuring units.