Abstract: The flood and draught, as well as the status quo of large and medium- sized reservoirs in Guangdong province were analysed here. Aimed at the problems in flood- control safety, active benefit and management operation, for the realization of foundation functions of reservoirs to the society and economy sustainable development, the sustainable utilization measures for large and mediumsized reservoirs in Guangdong province were advanced in six aspects, including optimization of reservoir functions, flood- control system, water quality entironment, management operation mechanism, informatization and talents squad construction.