Advances in the Analysis and Design of Marine Structures is a collection of papers presented at MARSTRUCT 2023, the 9th International Conference on Marine Structures, held in Gothenburg, Sweden, 3-5 April 2023. The conference was organised by the Division of Marine Technology, Department of Mechanics and Maritime Sciences at Chalmers University of Technology, in Gothenburg, Sweden.The MARSTRUCT Conference series deals with Ship and Offshore Structures, addressing topics in the fields of:Methods and tools for loads and load effectsMethods and tools for strength assessmentExperimental analysis of structuresMaterials and fabrication of structuresMethods and tools for structural design and optimizationStructural reliability, safety, and environmental protectionThe MARSTRUCT conferences series of started in Glasgow, UK in 2007, the second event of the series took place in Lisbon, Portugal in March 2009, the third in Hamburg, Germany in March 2011, the fourth in Espoo, Finland in March 2013,