A method for issuing a reliable certificate to a vehicle for a vehicle-to-anything (V2X) communication in a server on a network comprises receiving a certificate issue request including vehicle identification information and road-side unit (RSU) identification information from an RSU. Log information for the certificate issue request is extracted from a database. Normality or abnormality is determined according to whether a predetermined certificate issue criteria is satisfied by analyzing the certificate issue request and the log information. The certificate is issued and the certificate is transmitted to a vehicle communication module according to determination of normality, or certificate revocation information is registered according to determination of abnormality.