The invention discloses a system for simulating a USIM card in an LTE terminal test, comprising a test system, a man-machine interaction interface MMI, a terminal tested module, a simulated USIM module and an NV module; the method includes the following steps: S1, configuring NV test information ; S2. Read the configuration information and data items of the NV; S3. Set the data information of the simulated USIM system; S4. Use the information of the simulated USIM to search the network, use the data to authenticate the network, and use the simulated USIM system to replace the physical USIM card And update the information in the registration process in real time. The method and system proposed by the present invention have low production cost, convenient testing, automatic batch testing, and avoid test failure in abnormal situations. In the case of USIM card, card slot damage or poor contact of the machine card, the test can be continued. When the data of the physical USIM card is abnormal, you can directly enter the debugging work of the test case.