The invention discloses an urban water body maintenance method of a floating type water crop ecological industry chain. The urban water body maintenance method comprises the following steps : 1) takinglotuses as main water plants and matching with a proper amount of other water plants or landscape plants; 2) producing a water lilies boat; 3) combining the water lilies boat in place; 4) intensivelypicking crops and recycling sludge. According to the urban water body maintenance method of the floating type water crop ecological industry chain, a complete ecological pollution control chain period is finished and is circulated; a simple, firm, cheap and beautiful large-buoyancy loading vehicle is adopted, so that water crops are possibly planted in a large-size box, and an applicable water region of the method is not limited; a lot of underwater sludge is digested and the target of purifying water and increasing a water body capacity is realized; the water crops are planted in the large-size box in a large scale, so that development of an industry chain commonly composed of a floating planting industry and a derived tourist industry is possibly realized; in a whole process, expensivefacility equipment and a highly sophisticated technology are not needed, so that the method is simple and practical.