Amorphous chalcogenide As2S3, As2Se3, GeS2, GeSe2, Ge20As25S55, Ge20As25Se55, Ge10As40S20Se30 films were studied by femtosecond OHD-OKE. Ict was indicated that the third-order nonlinear susceptibility χ(3) was as large as 10-12 esu, and they also exhibited a very fast response time shorter than 200 fs. Their nonlinear refractive indices and absorption were also calculated from the above results. The ultrafast response and large third-order nonlinearity in amorphous chalcogenide films are attributed to the ultrafast distortion of the electron cloud of atoms.