Restricted Damerau-Levenshtein edit-distance is applied in many fields such as language processing, speech recognition, detecting theft of information, biology computation, etc. Modifying from the method of Mehryar Mohri (2003) which uses the composition of transducers combined with a single-source shortest-paths algorithm to compute Levenshtein edit- distance of the two languages, we propose a type of an extended automaton in order to compute the restricted Damerau-Levenshtein edit-distance of the two languages.