Some research achievements of immiscible alloy preparation with dispersed and homongeneous phase structure under micro-gravity and gravity environment have been summarized. The various effective factors on solidification of the immiscible alloy including nucleation

growth-diffusion-convection/diffusion

deposition and floatation due to gravity interfacial energy

Ostwald ripping

Marangoni motion

Brownian coagulation

the content of second phase and cooling rate are pointed. The unidirectionally solidified microstructures of the alloy are evolved from regular fibrous compound structure to regular array of in-droplets and then to random dispersion of in-droplets in the matrix. The varieties of preparation technology

including powder metallurgy

uni-directional solidification

simulated casting method under microgravity condition

stirring casting

rapid solidification

have been introduced based on the solidification characteristics. Meanwhile

the application of computer simulation for immiscible alloys including the dynamic density method

discrete particle method and phase field method has been shown. The problems and the future orientation in immiscible alloys have been also pointed out.