The present study addresses the question of whether the tongue rises as high as in the vowel /i/ in two types of Korean palatalization: a) when consonants take place before /i/ within a morpheme and b) when the consonants /t, th/ occur before /i/ across a morpheme boundary, changing into their affricate counterparts. For this purpose, we looked into stroboscopic-cine magnetic resonance imaging (MRI) data on tongue movements taken from two native speakers of the Seoul dialect. The MRI results that the tongue gradually rises and moves front throughout the target consonants are further confirmed by our acoustic data taken from ten Seoulites including the subjects in the MRI experiment. From this, we propose that Korean palatalization is a phonetic coarticulatory effect in the sense of Öhman (1966) and Keating (1985, 1988).