The term "epistemic cognition" refers to individuals' understanding of the nature of knowledge (i.e., what one believes knowledge is) and the knowing process (i.e., how one comes to know). Research on epistemic cognition has revealed three milestones in epistemic development. In early development, knowledge is viewed as a direct copy of reality ("absolutistic"). The next level of development views knowledge as mainly determined by one's personal point of view ("multiplistic"). The third level of epistemic development views knowledge as a joint function of perspective and reality ("evaluativism"). In order to clarify further how developmental change in adolescents' epistemic understanding contributes to the process of identity formation, the current study analyzed associations between various epistemic stances, on the one hand, and identity status scores, on the other hand, while simultaneously taking into account potential effects of individual differences in cognitive processing. In a cross-sectional and a longitudinal study, identity status scores of diffusion, foreclosure, moratorium, and identity achievement, as assessed by the Extended Objective Measure of Ego Identity Status, were analyzed as a function of adolescents' epistemic stance. The cross-sectional sample consisted of 200 German adolescents in grades 7, 9, 11, and 13; and the longitudinal study (18 months) involved 134 participants (mean age at retest of 16.5 years). The findings confirmed that the development of epistemic cognition contributes to adolescent identity formation. These effects were not due to individual differences in identity processing style. 6 tables, 1 figure, 43 references, and appended item examples of the Epistemic Development Questionnaire