This paper proposes a Tree-Based Ant Colony Optimization based on the positive feedback mechanism and uses it to resolve the Degree-Constrained Multicast Routing.The ant in the new algorithm chooses some link according to the possibility distribution and adds it into the multicast sub-tree

while it checks the node where the new link is added.If the node has reached its degree constraint

the ant will never choose the adjacent links of the node.Computational simulation and analysis show validity of the new algorithm.The simulation result shows that the convergence of the new algorithm is much faster than the old one

the performance of the resolution is better

and it also has a lower space complexity when used to resolve the degree-constrained multicast routing.