In this paper a new recognition system of distorted patterns is presented, where the Viterbi algorithm and a modified trellis incorporating a pertinent statistics of distorted patterns are used. The system works in a manner quite similar to our own human decision process. The trellis is so constructed that it can eliminate all the irrelevant pattern classes at the outset and leave only the most probable for its fimal decision, yielding a great economy of processing time and the accuracy of decision. The method was applied to recognition of handwritten English letters and Japanese Katakana's with success. The method is also universal and can be applied to any category of distorted pattems.