The invention discloses a method, a device and a system for optimizing network access performance, which are used for improving network optimization efficiency and accurately and effectively optimizing the network. The method comprises the following steps of: generating a detailed call tracking record according to the received call trigger message, wherein the detailed call tracking record is used for recording detailed information of the whole call flow, and at least comprises a call reason code; after the release of the current call, acquiring the detailed call tracking record, and judging whether the current call is successfully accessed according to the reason code therein; and counting the network access failure rate based on the judgment result, evaluating the network access performance according to the access failure rate, and selecting a corresponding reference optimization scheme for network optimization according to the evaluation result. Therefore, the automatic network evaluation can be realized, the accurate and effective network optimization can be automatically carried out, and the system maintenance cost is reduced. The invention also discloses a device and a system for optimizing network access performance.