In order to look for acoustic--phonetic reflections of focus in discourse, speech of Korean and Japanese was analyzed, followed by a perception experiment ensuring that, to locate the focus, a sufficient range of F0 change must exist in the focused phrase. The following findings are drawn from phonetic observations and the perception experiment. (1) In both Korean and Japanese the focus is realized by the difference in F0 in the syllables in the focused phrase rather than by its local maximum. Without a lexically preassigned pitch accent, the focus in Korean emphasizes the difference in the rise in pitch in the first two syllables of the phrase in focus. Japanese, on the contrary, makes use of the inherent accentual pattern of the phrase, resulting in comparatively higher F0 of the accented syllable. (2) The differences in intensity between focused and unfocused phrases are not significant, whereas the overall significance of the differences in pitch change is maintained both in Korean and Japanese; there is a tendency in Korean toward larger variational ranges than in Japanese. (3) Duration is longer for the focused phrase than for the unfocused; Korean shows more prominent lengthening of the focused phrase than Japanese. (4) According to the perception experiment, duration and intensity are not utilized to locate the focus in discourse; in spite of longer duration and stronger intensity, focus is not perceived without a sufficient change of F0.