The renovation and expansion of the double-line ship lock project on the existing hub of the first-line ship lock face difficulties in being limited by existing buildings and structures,as well as difficulties in effectively utilizing the structure scheme of the first-line ship lock.Combined with the double-line ship lock project of Fengguang hub of Dongjiang waterway,two existing ship lock utilization ideas and corresponding layout schemes are put forward:Plan 1 using the old ship lock structure as the new ship lock approach channel and plan 2 using the old ship lock as the cofferdam during the construction period.Comparison is conducted on the advantages and disadvantages of the two schemes in the current structure utilization,construction difficulty,land acquisition area and so on.In view of the problem of large land acquisition area in Plan 2,the optimization measures are put forward that the main lock is arranged on the river side and the small lock is arranged on the bank side,so as to make full use of the water and land space of the current lock and effectively reduce the land acquisition area.