Based on the nonlinear compression characteristics of the soil around the grouting in the process of compaction grouting, the soil ε-p curve model was established, and the parameters of the curve model were determined by the conventional test parameters. The compaction grouting expansion process was simplified to the cylindrical hole expansion model, derived the theory about influence radius of compaction grouting. The influence radius of compaction grouting is related to the compression characteristics of soil itself, grouting pressure, grouting quantity and grouting depth. From the field test of compaction grouting, we established the ε-p curve model describing the soil of the compaction grouting test site, recorded the construction parameters of compaction grouting, calculated the theoretical influence radius of the compaction grouting in the test site, analyzed the results of soil pressure monitoring and reinforcement effect at different distances of grouting holes, and verified the reasonableness of the theoretical formula of the influence radius of compaction grouting. The influence radius of compaction grouting can be used to determine the reinforcement range of grouting, and it has certain guiding significance in the design and construction of compaction grouting.