The aim of this paper is to compare New Keynesian and Post Keynesian economics on the theory of prices. In the past two decades, there has been a revival in explanations of price rigidity with the emergence of the "new Keynesian" economists. These economists try to explain the price stickiness that all of the empirical studies on the topic confirm. This paper takes up the question of whether these study findings are compatible with the Post Keynesian theory of prices. On a deeper level, the paper explores the compatibility between the new Keynesian and Post Keynesian theory of prices.