A modular ship complex includes a basic vessel provided with water height adjusting elements for varying the height of the waterline with respect to a pool of water forming a housing. The bottom of the housing is formed by a platform that is moved between a raised position and a submerged position by operating the water height adjusting elements to vary the height of the waterline. The ship complex includes equipped floating modules suitable for being inserted into the housing and to be extracted from the housing when the platform is in the submerged position. The modules rest on the platform when the platform is in the raised position. The modules include active operating elements integrated therein.