This paper investigates reconfiguration of metamorphic mechanisms as a typical character of topological change of the mechanisms. Metamorphic mechanisms with reconfigurable topology provide changed topological states and subsequently change the mobility to give various subphase mechanisms. This paper investigates the built-in spatial modules extended with metamorphic characteristics to develop a metamorphosis operation based on building blocks in the form of spatial kinematic pairs and associated links. The composition principle of a metamorphic mechanism gives the mechanism characteristics and generates subphase working mechanisms. These working mechanisms change and develop into different forms in an evolutionary process of topological change and the proposed module composition principle in metamorphic mechanisms leads to the development of module topology variation and reconfiguration operations based on algebraic properties of Lie displacement-subgroup. The topology transformation is further used for configuration aggregation and degeneration and all the linkage operations are based on set theoretic, leading to topological reconfiguration of metamorphic mechanisms that maps a source metamorphic mechanism into various subphase configurations. This paper demonstrates the principle with case studies from a metamorphic mechanism generator to subphase mechanisms and vice versa.