南京长江第四大桥为主跨1 418 m三跨连续悬索桥，结构体系复杂，世界范围内较为少见。本文通过对三跨连续体系悬索桥矢跨比、索塔区支撑、纵向限位及竖向限位的比较研究，详细阐述了该结构体系的受力特点，并结合南京长江第四大桥的实际情况，提出了适合的结构体系形式。同时，三跨连续弹性支撑体系在悬索桥中首次应用，具有创新意义。

With an extraodinary complex structure structure, the Fourth Nanjing Yangtze River Bridge, a three-span continuous suspension bridge, is scarce in the world. This paper is to elaborate the structure characteristic by comparing and analysising the following aspects： the span-rise ratio, support at cable tower, limitation of longitudinal displacement and vertical displacement, as well as to propose a propor structure system, three-span continuous elastic supporting suspension bridge structure system, according to the pactical issue of the Fourth Nanjing Yangtze River Bridge, which is of innovative significance.