We report the generation of terahertz radiation via optical rectification from a poled polymer using femtosecond optical pulses. We have measured the refractive index and power absorption in the terahertz frequency range. The corresponding difference frequency mixing coherence length in the poled polymer (1 mm at 1 THz) is ∼20 times greater than that of LiNbO3(50 &mgr;m at 1 THz). The observed far‐infrared electric field radiated from a 16 &mgr;m thick polymer sample is only 4 times smaller than that from a 1 mm thicky‐cut LiNbO3crystal. We discuss conversion efficiencies for thicker polymer samples. ©1995 American Institute of Physics.