Abstract: Based on the practical case of Songjiang Tram Line T1 in Shanghai, through difference analysis of physical and mechanical parameters of soil layer, the problem of tram subgrade uneven settlement in deep soft soil is studied by using finite element method. On account of settlement control, three sub-rail foundation design schemes are analyzed and comparatively selected, including pile-slab structure, filling replacement and composite foundation. Results show that the total settlement of tram subgrade in pile-slab structure scheme is 10.1~13.3 mm, the settlement control effect is relatively good.