A catalyst support with both small pores and large pores, as well as a distinct bimodal pore structure, has excellent advantages in industrial solid-catalysis reactions because the large pores provide pathways for rapid molecular transportation and the small pores serve a large area of active surface. A simple preparation method of bimodal supports was developed by introducing SiO2 or ZrO2 Sol into large pores of an SiO2 gel pellet directly. The pores of the obtained bimodal supports distributed distinctly as two kinds of main pores. On the other hand, the increased BET surface area and decreased pore volume, compared to those of original silica gel, indicated that the obtained bimodal support formed according to the designed route. The obtained bimodal support loaded with cobalt was applied in slurry-phase Fischer-Tropsch synthesis (FTS). The bimodal catalyst presented the best reaction performance in slurry-phase FTS with a high reaction rate and low methane selectivity, because the spatial promotional effect of the bimodal structure and the chemical effect of the porous zirconia were available inside the large pores of original silica gel.