This paper outlines the full lifecycle management system research on dredging transmission gearbox of dredger.Through lubeoil on-line detection and other auxiliary checking methods,a model is established for analyzing the wear&tear and potential faults for key moving parts of large transmission gearbox and the dynamic diagnosis and plan maintenance schemes are proposed for solvement of transmission gearbox,so as to improve the scientific&economic full lifecycle usage and maintenance for dredger transmission gearbox.