The third order nonlinear optical susceptibilities of cast films of diacetylene-containing polyamides, copolyamides and polyesters, were measured using degenerate four-wave mixing with picosecond pulses at 532 nm. The blue films of polyamides which contain aromatic polydiacetylene had chi(3) values of the order of 10(-9) - 10(-10) esu, while the orange films of polyesters having aliphatic polydiacetylenes showed chi(3) values of the order of 10(-10) - 10(-11) esu.