The present invention relates to an anesthetic absorbing circle, comprising: a first common tube, providing an anesthetic gas mixture an inspiration branch, connected to the first common tube and delivering the anesthetic gas mixture to a patient end an expiration branch, connected to the first common tube and sending back the expired gas from the patient end to the first common tube a second common tube, connected with the inspiration branch and the expiration branch at its first end and connected with the patient end at its second end and a flow sensor, wherein the flow sensor is disposed in the first common tube. Thus, according to the present invention, the flow sensor can conduct bidirectional monitoring, the flow sensor is remote from patients, and water accumulation at the probe will not appear in addition, the probe can be easily detached and disinfected at a high temperature, and can be used between adults and children.