土木工程是一門專業的工程學科，涉及物理和自然環境的設計、施工和維護，包括公共工程，如道路、橋梁、運河、大壩、機場、污水系統、管道、建筑物的結構部件和鐵路。土木工程傳統上分為若干子學科。它被認為是繼軍事工程之后第二古老的工程學科，其定義是區分非軍事工程和軍事工程。土木工程發生在從市政到國家政府的公共部門，以及從個人業主到國際公司的私營部門。

Civil engineering is a professional engineering discipline that deals with the design, construction, and maintenance of the physical and naturally built environment, including public works such as roads, bridges, canals, dams, airports, sewerage systems, pipelines, structural components of buildings, and railways.Civil engineering is traditionally broken into a number of sub-disciplines. It is considered the second-oldest engineering discipline after military engineering, and it is defined to distinguish non-military engineering from military engineering. Civil engineering takes place in the public sector from municipal through to national governments, and in the private sector from individual homeowners through to international companies.