Third-order optical nonlinearities of several polymer films doped with naphthalocyanine derivatives have been measured under resonant conditions by femtosecond degenerate four-wave mixing (DFWM). The metal substitution and the peripheral groups influence both the magnitude and the response of the third-order optical nonlinearities. Temporal profiles of the DFWM signal were measured with a time resolution of 0.3 ps and were found to consist of at least two components, the coherent instantaneous nonlinear response and the slow response. The latter for the films decayed much faster than that for the solutions due to effects of aggregation or intermolecular interactions. The electronic component of the effective third-order nonlinear optical suscepitibilities, χe(3), of the polymer films was evaluated and a film of poly(methyl methacrylate) doped with 20 wt% octabutoxy-substituted zinc 2,3-naphthalocyanine showed the largest χe(3) value of 8.9×10-9 esu. The results were compared with those in the literature.