An Autonomous Structural Health Monitoring (SHM) System for Fixed Offshore Structures is a tool used to monitor the state or the health of a structure in terms of its integrity and strength in an automated manner. An SHM system framework comprises of software and hardware integration equipped with IoT capability to collect raw data, online data transmittal to onshore, a back-end engine to process data into useful engineering information and display the monitoring results through engineering parameters and digital twinning, which emulates the real condition of the structure offshore. The prominent monitoring method for a structure's strength is through global monitoring, using structural modal properties as the measuring parameter to indentify a certain structure's global integrity, specifically using its natural frequency. This paper aims to layout the framework of an autonomous SHM system for global monitoring which is implemented onto a seismically vulnerable fixed offshore structure. Copyright © 2022, Offshore Technology Conference.