Abstract: In order to study the application effect of high-pressure rotary jet grouting anchor cable support in deep and weak soil layers, this article takes a deep foundation pit project in Nansha, Guangzhou as an example. The average thickness of the mud on the site is 30-55 m, and the support structure adopts the form of support piles and high-pressure rotary jet grouting anchor cables. Throughout the excavation period of the foundation pit, the support structure is always in a safe state, and all monitoring data meet the regulatory requirements. Through monitoring the entire process of anchor cable axial force, it was found that the measured value of anchor cable axial force is only about 55% to 60% of the design value, indicating that the anchor cable axial force has not been fully utilized and there is still great potential that has not been fully realized. It has good applicability in deep and weak soil layers. The application of the support form of this foundation pit can provide experience and reference for foundation pit projects in similar soft soil areas.