At present, water conservancy project in collapsible loess foundation treatment design has no specification, only “Code for Building Construction in Collapsible Loess Regions” (GB50025-2004) for reference, but the specification is mainly used in building engineering.Apparently, if the specification is applied to the channel foundation treatment design, the processing standard is too high to demand, witch can not sufficiently play channel''s excellent performance of having good adaptation to foundation deformation, and the investment is huge。Through theoretical analysis and combined with the actual engineering conditions, this paper proposed the design principle and method of channel engineering in collapsible loess foundation treatment and the three-dimensional stress deformation finite element structural analysis verification.The processing principle and method can meet the safety requirements for channel engineering.