Some questions of the amorphization mechanism of semiconductors during ion bombardment have been considered theoretically. The probability of the formation of crystalline disordered regions (CDR) and amorphous regions (AR)1has been calculated as a function of irradiation temperature T, atomic number Zi and ion enerw. It has been shown that the role of CDR in the amorphization process increases with the increase of T and decrease of Mi. The effect of irradiation temperature (T = −150, +25 and +1OO°C) on the silicon amorphization process during bombardment by light (B12), mean (Ne20) and heavy (Sb121) ions has been studied by various techniques: ir-absorption, ir-reflection and fast electron diffraction. It has been shown that the influence of irradiation temperature is stronger for light ions and large values ofT. Theoretical results are in good agreement with experimental ones.