In general, the end of question utterances is accompanied by a rising intonation. However, non-rising intonation is commonly observed in question utterances appearing in conversational speech. In order to clarify the factors involved in the choice of rising or non-rising intonation, in the present work, we analyzed question utterances extracted from Japanese conversational dialogue speech data of multiple speakers. Each utterance was categorized in terms of the question type, the phrase final intonation and the phrase final morpheme. Analysis results revealed that (1) about 20% of question utterances were neither accompanied by a rising intonation nor by a pitch reset; (2) among the question types, non-rising intonation appeared in more than 50% of "request for agreement", "open-type questions", "backchannel-type questions", and "self-directed doubt-type questions"; (3) regarding morphemes, non-rising intonation appeared in more than 50% of utterances ending with question-related final particles; in contrast, more than 80% of the utterances ending with morphemes other than final particles were accompanied by a rising intonation or a pitch reset. Copyright © 2013 ISCA.