In this paper, we investigate the relationship between turn-taking and syntactic/prosodic features based on a quantitative analysis of Japanese three-party conversations. We analyze parts of speech, F0 and energy values, and mora duration, showing that most of these features are related to turn-taking, and some of them show similar tendencies in different syntactic contexts. We also investigate the interrelation-ship among all the features with respect to turn-taking, and discuss roles of syntactic and prosodic features in turn-taking by comparing our results with previous findings related to the relationship between syntax and prosody in the decision process of turn-taking.