The concepts “Welfare” and “Security” while combined by the concept “Social” are of new ones born during modern developments. Because of such characteristic, they have got involved in modern social affairs and it seems impossible to make a clear and comprehensive definition for them so that all the experts have a common idea about it. But bringing their formations into account and their applications either, will lead us to a reasonable understanding of them. “Social Welfare” is used to indicate to a condition including economic, social and political one and focuses on human being, society accountability to human being and tries to promote the social potential as a whole in individual and group aspects. “Social Welfare” has although many things in common with social welfare, but has a different attitude toward the problems. In this article, a clear definition is represented for any of these basic items.