This paper studies the Morphological analysis and processing of noun forms in Arabic language. It focuses on the inflected noun forms and discusses the singular, dual and plural formation as well as case representation. The deterministic finite state morphological parser for the Arabic forms can deal with Morphological and orthographic features of Arabic and the morphological processes which are involved in Arabic verb and noun formation and declension. The Morphological analyser adds all the necessary information (prefix, suffix, stem, etc.) to each morpheme of the words; so the values will be added to each morpheme. Using Finite State tool to build the computational lexicon that are usually structured with a list of the stems and affixes of the language together with a representation that tells us how they can be combined together and how the network of all forms can be represented.