The invention discloses a building and calling method for a multi-resolution expandable coastline library. Aiming at the problems of incomplete coastline library data range, single resolution and low database expandability of an existing marine geographic information system and a charting imaging system, the building and calling method comprises the following technical steps of designing and managing a multi-resolution coastline library, calling the multi-resolution coastline library, cutting and forming a coastline user library, nesting and sequencing cut coastlines and the like, so that the problems are effectively solved; expandable library building of the multi-resolution coastlines is realized, and a user can randomly call the multi-resolution expandable coastline library; a user demand and the high-efficiency calling of the large-data-volume and multi-resolution coastline library are both considered; the building and calling method has a very important actual application value for seafloor topography charting, marine charting, marine information systems, computer graphics and submarine scientific researches.