Disclosed are a data access method and device. The method comprises: a terminal sending an authentication request to a server, the authentication request being used for requesting the server to verify whether a SIM card in the current terminal is a SIM car bound in the server by the terminal; if the terminal receives an authentication failure message, which is returned by the server, the terminal not permitting a user to access the data in the terminal, the authentication failure message being used for indicating that the SIM card in the current terminal is not the SIM card bound in the server by the terminal. The present invention can solve the technical problem in the prior art that the purpose of increasing data security is not achieved because the terminal and the SIM card are only in a binding state, and achieve the technical effect of increasing data security in the terminal.