Breathing machine air path system and breathing machine

The utility model belongs to the technical field of medical instruments, and particularly relates to a breathing machine air path system and a breathing machine. The breathing machine air path system comprises an air conveying module and an air and oxygen mixing module. The gas transmission module comprises a first mounting block and an adjusting assembly; the adjusting assembly comprises an air proportional electromagnetic valve and an oxygen proportional electromagnetic valve which are symmetrically distributed, and an air flow monitor and an oxygen flow monitor which are symmetrically distributed; the air conveying module comprises a second mounting block, a mixing chamber, an air connector, an oxygen connector, an air outlet connector and a third mounting hole are formed in the second mounting block, the air connector, the oxygen connector, the air outlet connector and the third mounting hole communicate with the mixing chamber, and the air flow monitor communicates between a first through hole of the fir