The aim of this study is to arrange and situate Bentham`s ``Pannomion``, to trace the theory of legislation by Bentham and thereby to propose(or gain) some useful perspective of the meaning of the principle of legislation. To perceive, at least access to the Bentham`s evaluation of legal and legislative theory, it is in its nature necessary to understand and conceptualize the line of Bentham`s theory of utilitarianism and ``Pannomion``. The line of Bentham`s thought, based on ``utility``, goes in phases further, critique of Common Law-rule(or law) in general-jurisprudence(analytical legal theory)-court and judicial process-legal reform and legislation (legislation and adjudication)-``Pannomion``(``Complete Code of Laws``). Bentham`s particular distaste for Common Law system and natural rights was a starting point of Bentham`s theory of legislation which inspired his earliest works. Bentham, in his lifelong academic writings, attacked both the practice and the theory of common law, so much as he tried to constitute a alternative entire system of law and legislation. Bentham argued it is impossible to have rights without a government or without law. Ultimately, maybe Bentham attempted to lay the foundation for the plan of the complete body of laws, ``Pannomion``, supposing it to be constructed aborigine, according to a method of division grounded on natural and universal principles. Bentham proposed the analysis of the ``idea of a complete law`` by identifying two qualities, ``integrality`` and ``unity`` which laid together established the individuality of law. To fix the individuality of a law was to ascertain what a portion of legislative matter must amount to in order on the one hand not to contain less, on the other hand not to contain more than whole law. And in the formation of such a work the sole proper all-comprehensive end should be the greatest happiness of the whole community governors and governed together, the greatest happiness principle should be the fundamental principle.