The independent loop line consisting of Line 3 and Line 8 of Suzhou urban rail transit system is studied, in order to implement the approved Suzhou urban rail transit construction plan. Qualitative and quantitative analysis is made on the necessity and possibility of the independent loop line by summarizing the layout characteristics of Suzhou city and drawing lessons from loop lines at home and abroad. Function analysis and comparison of passenger flow prediction indicate that there is lack of necessity in the independent loop line. Reserving a loop line of spoon type is feasible in civil construction, but the investment is huge, which will lead to great waste and social risks. The results suggest that “combined loop line + chessboard” network is more suitable for Suzhou city, a region with multicenters and unbalanced development.