Lubrication sealing system is a key component of the mixer.By taking the GK45E type banbury mixer as an example，its working principle and structure of the lubrication sealing system of rotor were introduced.Aimed at the poor sealing on sliding surface existed in the lubrication sealing system，common problems of high temperature alarms which caused by increasing of rotor end lubricant and discharged debris，and insufficient supplying of lubrication to the wear resistance ring，were analyzed and troubleshooting was carried out.