Abstract: In order to effectively utilize the waste silty soil and reduce the environmental pollution caused by traditional soil solidification agent, it is of great significance to develop a new environment-friendly soil solidification agent.The orthogonal test method of three factors and three levels was used to design nine groups of soil solidification agent test schemes with different mixing ratios, and the unconfined compression test was carried out.Then the range analysis and variance analysis were used to analyze the test results, so a optimal mixing ratio of composite soil curing agent was obtained.Finally, the effects of different solidification agent dosages and curing ages on the strength of waste silty soil were explored.The results show that the lime content in the composite soil solidification agent is the main factor affecting the strength of waste silty soil, followed by the content of nano-silica and slag.The unconfined compressive strength of waste silty soil with 10% composite soil solidification agent reaches the peak strength at the 28th day.