A method and an apparatus for acquiring and storing performance data of a cloud computing system are provided by the present application. The method is applied to each host in a cloud computing system, and comprises: acquiring local performance data according to a preset sampling period, parsing a user stack of a process using register values of a local CPU, so as to derive the function call chain of the process at the acquisition time and a DSO file corresponding to each function; and storing the acquisition time as a keyword and the performance data as a key value into a database correspondingly. A method, an apparatus and a system for detecting the performance of a cloud computing system are also provided by the present application. The method comprises: in response to a request from a user for detecting the performance of the cloud computing system, acquiring the target data correspondingly, and detecting the performance of the cloud computing system on the basis of the target data. With the present application, the distributed data storage is achieved, the unnecessary network overhead is avoided, and the performance data from a plurality of machines can be aggregated and parsed, and thus the performance analysis of the cloud computing system is realized.