Third-order nonlinear optical properties of chalocogenide glasses were investigated through third-harmonic generation (THG), optical Kerr shutter (OKS), and degenerate four-wave mixing (DFWM) measurements. We examined the dependence of the THG susceptibility on the absorption edge, thereby showing that the susceptibility rapidly increased as the absorption edge red shifted. Moreover, the THG susceptibility was compared with the OKS susceptibility. It was found that both susceptibilities almost coincided within the range of experimental errors. The OKS and DFWM experiments indicated that a high-speed compact optical switching device was obtained using the chalcogenide glasses. ©1997 American Institute of Physics.