Thec-axis resistivity ρc(H, T) of stage-4 MoCl5GIC between 1.9 and 50 K has been measured with and without an external magnetic field along the c axis (0≤H≤44 kOe). The interior G layers form a bottleneck to the c-axis conduction. The T and H dependence of ρcis mainly determined from that of the bottleneck resistivity proportional to the in-plane resistivity of interior graphite layers. A logarithmic behavior of ρcin the form of In(T) and In(H) indicates that the two-dimensional weak localization occurs in the interior graphite layers. The T and H dependence of the in-plane conductivity derived from ρcis discussed in terms of scaling relation predicted from the theory of two-dimensional weak localization.