With the development of the Internet and the rise of multicast, enabling multicast in a space division multiplexing elastic optical network (SDM-EON) is considered highly necessary. This paper focuses on the dynamic resource allocation for multicast in SDM-EON. First, to ensure service survivability and reduce the complexity of inter-core cross talk computation, we design a path-based strict cross talk avoidance routing, modulation, core, and spectrum allocation (PSCA-RMCSA) algorithm. Then, based on PSCA-RMCSA, a joint weight and PSCA-RMCSA (JW-PSCA-RMCSA) algorithm is proposed to further reduce the blocking probability (BBP) of services. Simulation results show that PSCA-RMCSA reduces the BBP by up to 7.55% and the resource allocation time by up to 88.63%, while JW-PSCA-RMCSA reduces the BBP by up to 10.43% and the resource allocation time by up to 82.11%, when compared to the shortest path tree RMSCA.