The tax convention is a treaty (most of the time bilateral) between states, so the main objective is to share the power of taxation between the signatory states in the case where the income or capital is taxable in both states. Niger, like every country in the world, has signed tax conventions in the context of international exchanges. These agreements aim to eliminate double taxation, however, the signatory countries must find their account. Interest is to see which of the OECD/UN conventions and the Franco-Nigerian convention is beneficial for Niger.The Franco-Nigerian convention is a convention that has not been modified since 1973 despite the number of finance laws modifying a good number of tax applications since 1973. In this context of mobilization of internal resources which is a major concern for Niger, a country in the grip of the vicious circle of poverty and underdevelopment, which of the Franco-Nigerian convention or the UN/OECD model convention is beneficial to Niger