Abstract: Objective: The impact of newlybuilt tunnel in sandy gravel stratum on adjacent existing tunnel is significant. To control existing tunnel deformation, it is necessary to study the deformation law and propose effective control measures. Method: Based on a metro interval tunnel project underpassing the existing one at small angle and close distance in sandy gravel stratum of Beijing, a combination of numerical simulation and field measurements is used to study the law of structural deformation caused by the above construction. The accuracy of the numerical model is verified. Through numerical models， the influence of the intersection angle between newlybuilt and existing tunnels on existing tunnel structure settlement is analyzed. The deformation control measures, including deephole grouting, pipe shed, grouting uplift, and horizontal jet grouting piles, are compared through the numerical models. Result & Conclusion: During tunnel underpassing construction, the impact of it on the vertical deformation of the existing tunnel structure directly above is significant. The impact decreases with the increasing distance away from the underpassing section. A smaller intersection angle results in wider settlement trough at existing tunnel bottom and larger vertical displacement values. The grouting uplift measure has the best deformation control performance, which is suggested for similar projects in stratum reinforcement.