This paper compares the value relevance of earnings under two different account- ing methods (namely, conservative accounting and mark to market accounting) in a competitive security market. It proves that the reported earnings are value relevant under both types of accounting methods. Furthermore, if the proportion of earnings ï¬Âxated traders lies in the upper range of the interval [0,1], the reported earnings under conservative accounting are more value relevant than the ones under mark to market. Otherwise, the reported earnings under mark to market are more value relevant than the ones under conservative accounting.