Abstract: A 324 MHz Alvarez-type drift tube linac（DTL） is used to accelerate the H-ion beam from 3 to 80 MeV for China Spallation Neutron Source（CSNS）, DTL contains 161 electric quadrupole magnet drift tubes with outer diameter of 140 mm, small volume, complex and compact structure. Due to space constraints, the quadrupole magnet coil in the drift tube adopts the advanced SAKAE structure, it is preliminarily processed on a whole piece of oxygen free copper and developed through electroforming, wire cutting and other processes. The outer diameter of the coil is 82 mm, the inner diameter is 37 mm, and each pole has 3.5 turns. The coil has the advantages of small volume, easy cooling and large excitation current, it is developed and used for the first time in China. In this paper, the development method of SAKAE coil is studied, the magnetic test and the heating test and analysis of the coil under high current are given.