Polyacrylonitrile (PAN) porous fiber containing titanium dioxide (TiO2) nano particle was fabricated using a wet spinning method. In order to produce continuous wet spun fiber from TiO2 nanoparticle filled PAN solution, the PAN solution as spin dope was prepared using dimethyl sulfoxide (DMSO) as solvent at various concentrations. We have successfully produced PAN/TiO2 porous fibers under conditions such as 15 wt% PAN and 0.5 wt% to 2.0 wt% TiO2. The rheological behavior of the PAN/TiO2/DMSO solution was characterized by oscillatory shear rheology under different conditions, including temperature and concentration. The effect of absolute value of complex viscosity on the wet-spinnability of the TiO2 nano particle filled PAN/DMSO solution was discussed. The PAN/TiO2 fiber was stabilized continuously in temperatures from 250 °C to 300 °C in air and carbonized at 800 °C in N2. The photocatalytic activities against methylene blue of PAN/TiO2 porous fibers by wet spinning was analyzed by the maximum absorption intensity at 664 nm in the UV-VIS spectrum during UV irradiation time and compared with that of the PAN/TiO2 nanofibers prepared by electrospinning.