The importance of maintain lake & river water healthy during sponge city construction is analyzed and the measures for lake & river water conservation and ecological restoration are discussed. It is believed necessary to protect the existing lake & river water sponge, restore the damaged water sponge, moderately construct new sponge in lake & river basin and manage the lake & river water sponge scientifically. Thus a sponge city with healthy eco-system and beautiful environment, which is able to retain and discharge water, adjust wet and dry and use multiple water sources, is constructed.