Abstract: Objective: Currently, with an increasing number of metro tunnels crossing existing railway subgrades, there is relatively insufficient study on shield tunnel oblique underpassing operating railways in soft soil area, thus it is necessary to investigate the deformation law of subgrades in such situations. Method: The interval shield tunnel engineering of Shaoxing Rail Transit Line 1 Datan Sta. to Railway Sta. underpassing Shaoxing Railway Station building and six railway tracks on Hangzhou–Ningbo Intercity Railway (Hang–Yong Railway) is taken as study case. Finite element method is employed to analyze the impact of shield tunnel excavation on the deformation of Hang–Yong Railway subgrade, and the comparative analysis of numerical simulation results based on fieldmeasured data fully validates the effectiveness of the sleeve valve pipe grouting reinforcement scheme. Result & Conclusion: The finite element analysis results show that the maximum settlement value of Hang–Yong Railway subgrade surface reaches 13.12 mm when the foundation reinforcement in shield crossing area is not considered, failing to meet the settlement control standard. However, when sleeve valve pipe grouting reinforcement measure is implemented in the shield crossing area, the maximum settlement value of Hang–Yong Railway subgrade surface decreases to 8.20 mm, meeting the settlement control requirements. This demonstrates the effectiveness of this measure in controlling the railway subgrade settlement and track irregularity. The fieldmeasured results show that the cumulative deformation process during the construction period of shield tunnel underpassing railway can be divided into four stages: subgrade heave, subgrade rapid settlement, subgrade stable fluctuation and subsequent settlement. The initial heave amount is large, while the subsequent deformation is relatively small. The cumulative deformation amount of the reinforced subgrade can be controlled within 10.00 mm.