Modern theorists keep telling us that public opinion does not necessarily lead to democratic virtues. The pursuit of personal interests by rational individuals does not necessarily lead to common good. This has become the reason why Bentham is criticized by others. However, if we return to the era of Bentham, we can find that these thesis ignore the connection between Bentham's idology of public opinion and his democratic theory. Bentham believes that the value of democracy is not only re?ected in the one-person, one-vote election system, but also in the broader government activities. Compared with majority tyranny and public opinion autocracy, whether to build a good government responsible for the people is the key to determining the success of democracy; public opinion is the most important means to ensure that the ruler is responsible to the ruled outside the electoral system, whose operation is embedded in the public opinion tribunal:That is, moral sactions are imposed on the abuse of power by the ruler through the check of government information, making it the most important social force to achieve the common good.