Catalytic performance is sensitive to the catalyst preparation method and type of catalyst precursor. To investigate the effect of catalyst precursors on physicochemical properties and efficiency of Fischer-Tropsch synthesis (FTS) process, SiO2-supported Co catalysts were synthesized via an incipient wetness impregnation method from four different precursors: Co(NO3)(2) (Co-Nit), Co(C2H3O2)(2) (Co-Ace), CoCl2 (Co-Chl), and Co(OH)(2) (Co-Hyd). Our study reveals the type of Co precursor used during synthesis has significant effects on catalyst dispersion, size, crystalline phase, reducibility, stability, and FTS performance. In particular, catalysts derived from Co(NO3)(2) and Co(OH)(2) show superior CO conversion and C5 + selectivity than those from Co(C2H3O2)(2) and CoC1(2), which is consistent with their reducibility. C5 + selectivity increases in the following order: Co-Chl < Co-Ace < Co-Nit < Co-Hyd. C5 + product distributions for Co-Ace, Co-Chl and Co-Hyd are mainly in the diesel range (C-12-C-17). In stark contrast to Co-Nit that shows a relatively flat product distribution, that of CoHyd is centered on C-15. Prenatal and postmortem characterization of the catalyst reveal sintering and formation of Co2C in all catalysts except Co-Nit, which may explain the various degrees of deactivation observed. Further, XANES and EXAFS data confirm the superior structural stability of Co-Hyd and presence of hydroxyl groups even after reaction.