Abstract:The inner trade of multinational corporate sets up "inner market" which is different from the common market.The inner market has certain economic rationality but results in the problems in taxation and tax laws and leads to the reduction of legal effect.As a result,tax laws should be used to standardize the inner market and use the relative measures to realize interests balance between main bodies so as to "effectively enforce laws and regulations".However,the inner market is "a typical complex issue",the laws and regulations about taxation have inevitable limitations,thus,"comprehensive laws and regulations" for "inner market" are needed from the legal angle of tax law,financial law,competitive law,environmental law,international law and so on and from the non-lawful angle of economy,politics and so on.