When closing an international contract, both contract parties endeavor to convey their intentions from the stage of negotiation to the moment of signing the contract. Of the many problems presently related to contract language, the first one to consider is which contract party will run the risk of the language deficiencies occurring as a result of the misunderstanding and misinterpretation between different languages. The second problem to consider is whether the interpretation and translation of the contract language is needed and, if so, which party is going to bear the expenses and assume responsibility of the misinterpretation in the translation of, the contract language. The third problem is related to the obligation of explaining to both contract parties the contents and details of the international contract written in different languages. The fourth issue is which language of both contract parties becomes the standard contract language in the procedure of arbitration. The fifth, but not the last problem, is how to solve the language defects in interpreting and translating the contract languages. These five problems can be easily solved by the approval of the contract parties in scrutinizing and selecting the contract languages. However, this research mainly focuses on which effects of the contract language and as how to define and select the contract language.