According to the principle of fractional calculus, a unified model of arbitrary order partial differential equation (PDE) based noise reduction was proposed. The design method based on the numerical solution for arbitrary order PDE filter was realized. In particular, the filter features of arbitrary order PDE were analyzed. The numerical procedure has rapid implementation of the filtering procedure with one iteration, which has good time-consuming performance. De-noising tests were conducted on different degrees of artificial noise. Experimental tests have been rigorously compared with different de-noising methods to verify the efficacy of the proposed method. It turns out that the numerical process to PDE noise reduction has an excellent performance and a simple algorithm.