This paper is concerned with measuring the amount of syntactic information contained in prosodic features of Japanese utterances. Five prosodic features are employed, and the statistical relationship between those features and the inter-phrase dependency distance is estimated by using training data. Then parsing experiments are conducted in two different ways:one utilizing the posterior distribution of the interphrase dependency distance given the prosodic feature values, and the other without using such information. It has been shown that significant improvement in parsing accuracy is attained by utilizing the prosodic information, and that the duration of pause between adjacent phrases is more effective than prosodic features related to the fundamental frequency and the power.