A sand injectite phenomenon is recognized in the Zhujiangkou Basin of the South China Sea through an analytical comparison of core, well logging and seismic data with those reported abroad. Their Gamma curves are almost box-shaped and the dipmeter logs are unorderly, casually with a high-and-steep dip. Thus, this phenomenon in seismic profiles indicates a winglike or conform intrusion, which, however, exclusively suggests sand injectites on a relatively large scale.