La-TiO2 nanofibers are prepared by a sol-gel assisted electrospinning method. The structure and morphology of La-TiO2 nanofibers are characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). XRD analysis shows that the weight percentage of anatase and rutile in the 1.5 mol% La-TiO2 nanofibers calcined at 600 degrees C is about 8:2, which is similar to P-25. The XRD data of La-TiO2 nanofibers with different La content shows that La3+ dopant has a great inhibition on TiO2 phase transformation. The photocatalytic activity of the as-prepared La-TiO2 nanofibers is evaluated by photocatalytic decolorization of Methylene Blue (MB) aqueous solution. The results show that the 1.5 mol% La-TiO2 nanofibers calcined at 600 degrees C exhibit high photocatalytic activity, indicating that 600 degrees C and 1.5 mol% are the appropriate calcination temperature and optimal molar ratio of La to Ti, respectively.