Two experiments were conducted to examine the role of Kulja and morpheme in processing two-syllable Sino-Korean words. In Experiment 1, the effects of morphemic frequency were not significant at the initial and final positions of a word while Kulja frequency and Kulja-morpheme correspondence at both positions in a word had a significant impact on the processing of nonwords. Lexical decision times were longer for nonwords with high frequency Kulja and for nonwords with ambiguous Kulja-morpheme correspondence whose Kulja can go with many different morphemes. In Experiment 2 Kulja-morpheme correspondence was examined for words as well as nonwords. Lexical decisions were slower for stimuli with ambiguous Kulja-morpheme correspondence. The effect was more stable for nonwords, which replicated the result of Experiment 1. In sum, the results of this study suggest that words with ambiguous Kulja-morpheme correspondence activate many different morphemes and competition among these morphemic candidates slows down the lexical selection process. Kulja frequency, Kulja neighborhood, morphemic frequency, morphological neighborhood, and Kulja-morpheme correspondence in Korean word recognition were also discussed.