A Ti doped carbon nanofiber (Ti/CN) catalyst was synthesized and investigated as a novel heterogeneous acid catalyst. The Ti/CN catalyst was prepared by electrospinning, preoxidation and carbonization. The fiber morphologies were characterized by scanning electron microscopy (SEM). FT-IR spectra were used to characterize the chemical structure of fiber mat. The X-ray diffraction spectroscopy (XRD) characterization demonstrated the formation of turbostratic graphite structure in carbon fiber. The catalysis results showed that the Ti/CN catalyst was very efficient for the acetalization reaction with yields over 87 %. Moreover, the larger fiber structure made the recovery of Ti/CN conveniently and the Ti/CN catalyst could be reused for five times without loss of initial activity.