The main objective of this paper is to present the results of empirical studies on the impact of internal factors that determine the short-term reaction of Warsaw Stock Exchange on the dividend payment. The main research hypothesis states that market share price is decreasing on ex-dividend day. This hypothesis is operationalized by two sub-hypothesis. Hypothesis H1 states that the drop of ex-dividend day is lower than dividend per share. Hypothesis H2 stands that this drop depends on the internal determinants of ex-dividend day return.The theoretical part of the paper provides an overview of literature research on the evolution of share market price on ex-dividend day. In addition, the determinants of such changes were presented and shortly characterized. The empirical part of this article presents the results of
research on the impact of dividend form, dividend payout ratio, stability of dividend payments and capital structure on ex-dividend day return.