The present study sought to examine the meanings and the discourse functions of the auxiliary particle ‘man’ in Korean texts and discourses in order to apply to Korean language education. To this end, 3,994 examples extracted from Korean written and spoken corpus were examined. The results suggest that the particle ‘man’ has three meanings: (a) limits of objects, events and situation, (b) limits of scope, and (c) emphasis of degree. The particle ‘man’ has the implication of negation of all excluding the preceded words. Furthermore, the distributions of the particle ‘man’ are changeable according to its meanings and contexts. The grammatical items related the particle ‘man’ are ‘man+un (만은), man+i (만이), man+do (만도), man+uro (만으로)’ and ‘ppun+man+anira (뿐만 아니라), N+man+V+umyun (N만 V으면)’ etc., considering the degree of fossilization and transition of their meanings. The particle ‘man’ also has many discourse functions: (a) revising a hearer’s premised expectation or general premised expectation, (b) expressing a speaker’s negative attitudes towards given events or situations, and (c) serving as a discourse strategy to express a speaker’s politeness and to reduce the burdens of a hearer.