A cooling system and a wind power generating set. The cooling system comprises two cooling sub-systems thermally coupled to each other. Each cooling sub-system comprises: a first cooling circuit for cooling a first heat-generating component, a second cooling circuit for cooling a second heat-generating component, a third cooling circuit for cooling a third heat-generating component, a fourth cooling circuit for cooling a fourth heat-generating component, a pump station unit and a heat dissipation unit. The first cooling circuit and the fourth cooling circuit are connected in parallel to form a first branch, the second cooling circuit and the third cooling circuit are connected in parallel to form a second branch, and the first branch and the second branch are connected in parallel, and are connected to the pump station unit and the heat dissipation unit. The cooling system may achieve the fault-tolerant operation of two cooling sub-systems.