Cross-sectional transmission electron microscopy (XTEM) has been applied to the study of the growth kinetics of hexagonal MoSi2 on (001)Si. Growth rates, interface structures, and microstructures in the growth layers were determined for samples annealed at 560-580 °C for various periods of time. The silicide thickness was found to be proportional to the square root of annealing time. The activation energy and the rate constant of the growth were measured to be 2.3 eV and 14 cm2/s, respectively. Growth mechanisms are discussed. The results of the previous studies on the MoSi2 growth are summarized. Advantages of the present approach in the study of the growth kinetics of silicides on silicon, both in sample preparation and in the employment of XTEM technique, are outlined.