The major purpose of this paper is to explore educational researches in postmodern condition. First of all, the study examines the development of modernity and modernization, probing into their crisis and explaining the background of emerging postmodernism. The second part of this study explains the main position of five representatives of postmodernists: Lyotard, Derrida, Rorty, Baudrillard and Foucault. Finally, in three aspects of metaphsics, epistemology and methodology, this study analysis how educational researches adjust under the positive and negative influences of postmodernism. In concluding remarks, this paper maintains that postmodernism opens a field of vision for educational researches, but it seems to destroy old theories and methods rather than to build new ones. To be a mature study, postmodernism need more exchange with other studies.