Two cloud-resolving models (SCALE and VVM) take different pathways toward convective self-aggregation (CSA) in the radiative-convective equilibrium simulations, although they have similar domain-averaged properties. Analyses in the moisture space show that radiative cooling in the dry area mainly drives CSA in SCALE, while subsidence triggered by the convection in the moist region dominates in VVM. The change in the convective structures is found on the isentropic diagram in VVM, but this transition is unclear in SCALE. The object-based analysis provides that the convective systems with larger sizes are rare in SCALE. In contrast, large-size convective systems frequently develop in the moist region as CSA evolves in VVM. The large-size systems can efficiently drive the circulation between the dry and moist areas. The different pathways to CSA are associated with the transition of convective structures, which provides a new insight to understand CSA among cloud-resolving models based on the perspective of the mechanism.