Certificate updating method and system for application program client

The invention provides a certificate updating method and system for an application program client. The certificate updating method for the application program client comprises the steps of determiningwhether at least one target server meeting a specified condition exists in associated servers associated with the application program client or not; wherein the specified condition is that the root certificate corresponding to the associated server is updated; if yes, obtaining a latest target root certificate corresponding to the target server stored in a root certificate server; and storing thetarget root certificate, so that the application client verifies the target server by using the target root certificate when accessing the target server. According to the certificate updating methodand system for the application program client, the certificate of the application program client can be updated under the condition that a user does not perceive without updating the application program client, the usability of