A System-of-Systems (SoS) is a collection of systems, which consists of independent constituent systems to achieve higher-level goals. As an SoS changes constantly due to external and internal factors, dynamic reconfiguration and evolutionary development must be performed effectively. To manage an SoS that has these characteristics, SoS managers and engineers need to model and verify an SoS that accommodates changes. While many researchers have proposed techniques for modeling and verifying an SoS, little attention has been paid to the verification of a continuously changing SoS. Since the size and complexity of SoSs are too great to apply existing verification techniques, an efficient verification method for dynamically changing SoSs is required. If we can detect the change-related goals of an SoS and the corresponding change-affected parts in an SoS model, we can slice the SoS model in our area of concern and verify the SoS model efficiently. This paper proposes SoS GaP slicer, a verification method that considers the dynamic reconfiguration and evolution of an SoS. Our method could save the cost of verifying the whole of an SoS model by an efficient statistical model checking for SoSs. The experimental results show the accuracy and efficiency of the proposed method.