The objective of this paper is to investigate the possibility of using key word analysis of corpus linguistics methodology in the translation quality assessment in legal genre. The conventional approach in translation quality assessment focuses on the achievement of equivalence between the source text and the target text. However, this kind of strong emphasis on preserving the letter of law often disrupts the understanding of the target reader, thus causing default in securing the same legal effect intended in the translated legal text. Against this backdrop, this study adopts more reader-oriented approach in legal translation quality assessment based on the concept of textual fit proposed mainly by Biel (2014). Focusing more on the expectancy norm of the target audience, this mode of assessment evaluates the extent to which the translation fits into the non-translated convention of the relevant sub-genre of legal language, thus lessening the cognitive processing efforts of the target reader. This paper suggests a model for assessing textual fit by examining the overused lexical, grammatical and semantic patterns of English-translated Korean statutes compared to non-translated English statutes, based on hierarchical key word analysis results provided by Wmatrix.