The invention relates to a CRM system anti-unauthorized implementation method and device and a storage medium, and the method comprises the steps: obtaining a service name of a to-be-called service ina CRM system, and obtaining a service configuration table corresponding to the to-be-called service according to the service name; obtaining an authorization module code set corresponding to the to-be-called service according to the service configuration table, and judging whether the operation job number has the module permission or not according to the authorization module code set; if so, judging whether the to-be-called service has an identity authentication anti-detour identifier or not according to the service configuration table: if so, obtaining a user number corresponding to the to-be-called service, and judging whether the user number passes the identity authentication or not: if so, calling the to-be-called service, and if not, not allowing to call the to-be-called service. According to the invention, double security reinforcement is carried out on the CRM system, services without functional module permission are prevented from being illegally called, illegal business handling by bypassing customer identity authentication is avoided, unauthorized and illegal access is prevented, and the security of the CRM system is greatly improved.