In order to solve the problems of poor lubrication effect,low efficiency of manual application and high working intensity,an automatic spraying device for lubricating grease in the inner wall of the crane telescopic boom is designed.The device is composed of automatic walking system,spraying system,electrical system and heating system.Through system control,the automatic spraying of lubricating grease in the telescopic boom is achieved.The practical application shows that the device can effectively improve the automation degree of the telescopic boom assembly,improve the lubrication effect of the grease on the inner wall of the crane boom,reduce the labor intensity and improve the production efficiency,this device provides a technical support for the automatic lubrication process of the inner wall of the boom structure.