This paper presents a novel distributed probe system to measure the performance of the network in the cloud service system. Specifically, a three-layer architecture is designed to support a large number of network probes. Furthermore, the probes, which are used to implement the measurements across networks, have negligible influence on the entire network. Compared with the existing methods, our approach is more flexible and adaptable to the large-scale network. Our method can be adapted to the network in various kinds of cloud service systems, including private, public and hybrid ones. Moreover, the performance data will be returned in real time. By utilizing a statistical algorithm to analyze the data, our system will give the Cloud Service Administrator (CSA) a better and deeper evaluation of the situation of the network in the cloud service system. Experimental results demonstrate that our system is efficient and practical.