Two multicast protocols are proposed for deflection-routed all-optical packet-switched networks. One scheme sends a deflected multicast packet back to the root node while the other sends it back to the deflection point. Both schemes can be implemented using demonstrated optical signal processing technology. The performance of the two proposed multicast schemes are compared using Manhattan street networks. We found that the back-to-the-root-node scheme performed better than the back-to-the-deflection-node scheme. A hybrid approach can further improve the system performance.