Pb_1-xSn_xTe crystal growth under microgravity is reviewed and effects of microgravity on crystal growth are presented. Some issues for utilizing microgravity conditions are also described. Determination of diffusion-controlled steady-state growth conditions, estimation of Marangoni effect and computer simulation of thermal convection in the Pb_1-xSn_xTe melt performed on the ground are included. The growth experiment was carried out by the directional solidification method in the SL-J/FMPT mission on board the space shuttle “Endeavor” in 1992.