In a strong acidic environment, ordered earthworm-like mesoporous silica has been synthesized with CTAB templating and fluoride ion as a counterion. The synthesized products were characterized by small-angle X-ray diffraction (SXRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), N-2 adsorption-desorption isotherms, and Fourier-transform infrared spectroscopy (FTIR). The effects of F/Si mole ratio on the morphology, surface area, and the pore size of the sample were discussed. It was found that a F/Si mole ratio at 0.083 induced the formation of 3D hexagonal mesophase, whereas higher F/Si mole ratios led to the formation of 2D hexagonal mesoporous silica, the optimum molar ratio of F/Si for the formation of delicate earthworm-like mesoporous silica was observed at 0.250. The effects of the F/Si mole ratio, surfactant chain length, acid concentration, and shear flow on morphology were also studied.