A compressor system comprising: a driving unit configured to rotationally drive and including a drive shaft which is configured to rotate about an axis; a plurality of compressors (31,32) configured to compress a gas; and a transmission mechanism configured to increase a speed of a rotation of the drive shaft and transmit the rotation of the drive shaft to the plurality of compressors, wherein the transmission mechanism includes a main shaft which configured to rotate together with the drive shaft, a main gear fixed to the main shaft, and a plurality of gear mechanisms disposed to surround the main shaft, wherein each of the plurality of gear mechanisms is configured to transmit a rotation of the main shaft to a corresponding one compressor, and each of the plurality of the gear mechanisms includes an auxiliary gear meshing with the main gear, an auxiliary shaft to which the auxiliary gear is fixed and which configured to rotate together with the auxiliary gear, a plurality of first gears disposed apart from each other in a circumferential direction to surround the auxiliary shaft and configured to rotate together with the auxiliary shaft, an output gear meshing with the first gear, an output shaft to which the output gear is fixed and which is connected to each of the plurality of compressors, a first bearing rotatably supporting the auxiliary shaft, and a second bearing rotatably supporting the output shaft. a driving unit configured to rotationally drive and including a drive shaft which is configured to rotate about an axis; a plurality of compressors (31,32) configured to compress a gas; and a transmission mechanism configured to increase a speed of a rotation of the drive shaft and transmit the rotation of the drive shaft to the plurality of compressors, wherein the transmission mechanism includes a main shaft which configured to rotate together with the drive shaft, a main gear fixed to the main shaft, and a plurality of gear mechanisms disposed to surround the main shaft, wherein each of the plurality of gear mechanisms is configured to transmit a rotation of the main shaft to a corresponding one compressor, and each of the plurality of the gear mechanisms includes an auxiliary gear meshing with the main gear, an auxiliary shaft to which the auxiliary gear is fixed and which configured to rotate together with the auxiliary gear, a plurality of first gears disposed apart from each other in a circumferential direction to surround the auxiliary shaft and configured to rotate together with the auxiliary shaft, an output gear meshing with the first gear, an output shaft to which the output gear is fixed and which is connected to each of the plurality of compressors, a first bearing rotatably supporting the auxiliary shaft, and a second bearing rotatably supporting the output shaft. an auxiliary gear meshing with the main gear, an auxiliary shaft to which the auxiliary gear is fixed and which configured to rotate together with the auxiliary gear, a plurality of first gears disposed apart from each other in a circumferential direction to surround the auxiliary shaft and configured to rotate together with the auxiliary shaft, an output gear meshing with the first gear, an output shaft to which the output gear is fixed and which is connected to each of the plurality of compressors, a first bearing rotatably supporting the auxiliary shaft, and a second bearing rotatably supporting the output shaft.