This paper aims to suggest Middle and Medio-passive categories in Korean with cross-linguistic data. K. Kim(2009) argues that there are three kinds of non-active Voice categories in Korean: I-inchoatives, Zero inchoatives and Passives. I, however, argue that I-inchoative and Zero inchoative show morphological, distributional and semantic differences, and thus they should be respectively categorized into Middle and Anticausative. The so-called –i morpheme is regarded traditionally as passive morpheme, but I show that it is not just a passive but Non-active Voice morpheme in Korean. I have also argued that Medio-passive constructions should be assumed in Korean, because cross-linguistically they show distributional and semantic differences from middles and passives. An Instrumental phrase and an Agent phrase or an Agent phrase and‘by itself’can appear together in the medio-passives, and semantically they can have middle interpretation too.