Aiming at the problem of the construction benefit of short-slung distance for cutter suction dredger，this paper takes the dredging project of west basin of Lyusi Port in Qidong，Jiangsu as an example，studies the cutter suction dredger’s construction technology of the single-pump without necking and the double-pump construction with necking under the condition of short-slung distance，matches the head provided by the mud pump with the resistance of the pipeline by theoretical calculation，contrasts the main construction parameters of the single pump and double pump construction，such as the traverse speed，flow speed and concentration，and compares the productivity and production benefit of single pump and double pump construction. The results show that compared with single pump construction，the profit of double pump construction of Tianji ship can increase about 226，800 yuan/month，and the productivity of double pump construction can increase 22%.