As additive manufacturing (AM) evolves to become a common method of producing final parts, it will have the potential to significantly improve supply chain operations. The purpose of this thesis is to investigate the impact of adopting AM on supply chain. Three supply chain scenarios are investigated in this thesis, namely traditional supply chain, centralized AM-based supply chain and decentralized AM-based supply chain. Based on a cost model created in Excel spreadsheet, using data acquired from the existing literature and assumptions, this thesis compares three supply chain scenarios in terms of the optimal quantities and total costs under deterministic and stochastic demand. This thesis aims to explore whether the spare parts supply chain adopting AM technology is really superior to a traditional one, by comparing the total cost of each system