This article aims at shedding light on the concept of postmodernism, and its implications in TESOL. Postmodern philosophy as a prevalent concept and a hot buzzword in philosophy, science, and art is believed to have influenced TESOL theoretically in some ways. The elements of postmodernism including: constructivism, subjectivism, relativism, localism, and pragmatism are found to have been applied in TESOL to the concept of the demise of the methods, more focus on styles, strategies, multiple intelligences, chaos/complexity theory and critical theories. But in practice, in Iran TESOL still lives in the modem era.