Abstract: This paper Proposed a new composite curtain grouting technique, which solved the bearing layer defection problem of pile in the gravel filling karst area, weathering granite region and gravel zone. This technique prevented high pressure jet flow of composite grouting cutting the soil around the pile directly. Thus the bearing capacity of pile foundation could he guaranteed. Basing on the principle, the construction technology, described parameters of the new composite curtain grouting and the correctness of this method was verified. The new curtain composite grouting technique provided a reference for similar projects.