A two-step method to develop polyphophazenes containing the indole-based chromophores was presented. A polyphophazene with indole as side chains was first synthesized and then the post-azo coupling of p-nitrobenzenediazonium fluoroborate toward the indole ring afforded a multifunctional indole-based chromophore functionalized polyphophazene. The polymer exhibited excellent solubility in common organic solvents.