Methods and systems for authenticating devices using 3GPP network access credentials for providing MEC services. A device is configured to receive MEC services from an EAS through 5G S A or NSA architecture. The device is authenticated by an ECS, which involves validating a MAC generated by the device. The MAC is validated using an edge authentication key, which is generated based on 3GPP network access security credentials of the device. The device is authorized by an EES to receive MEC services, which involves successful registration of the device with the EES and the EES providing credentials to the device for accessing an EAS providing desired MEC services. The EAS provides the desired MEC services to the device if the device provides credentials to the EAS, which are same as those provided to the device by the EES.