By use of trap lamp it could change the fly direction of the insects of agriculture, forestry, animal husbandry, flower, fruit, vegetable and water living insects to the crab raising pool. Near 300 species of attracted insects could be preyed by crabs. The weight of the attracted insects each year was 90.3～114.1?kg per lamp from May to Oct.. Each crab could eat 19.62 insects per night. The harmful insects could be changed to the high quality food for the crab growth. And production of crab (could be increaed to 118.35 ?kg/hm 2), 22.28% of the rate of increasing and 9?468.00～14?202.00?yuan/hm 2 of the income in the trap lamp attracted pool area compared the CK area. On the same time, trap lamp could attract and kill the large number of insects of agriculture, forestry, animal husbandry, flower, fruit, vegetable and water living insects to crab pool and they could be all preyed by crabs.