The optimal amount of 15 wt%Co/10 wt%K/Al2O3 catalyst was prepared using the impregnation technique in order to study the kinetics of the Fischer-Tropsch synthesis. The rate of synthesis was measured in a fixed-bed micro reactor with H2/CO feed ratio of 1-3 and space velocity in the range of 2,700-5,200 h^(-1) under reactor pressure of 8 bar and a temperature range of 210-240℃ . The experimental data were best fitted by a Langmuir-Hinshelwood-Hougen-Watson (LHHW) approach rate in the form of -rCO=(k2K1PCOPH2)/(1+K1PCO). Furthermore, the data were fitted fairly well by a power law equation in the form of -rCO=kPCO 1.32PH21.42. The activation energies for LHHW approach model and power law equation were obtained as 138.5 kJ/mol and 87.39 kJ/mol, respectively.