This study examined how adult native speakers of Korean prosodically structure their speech during spontaneous story telling. It asked participants to produce a spontaneous story from a picture book in L1 Korean. Participants’ phonological phrasing (via pause) was analyzed with reference to eight hierarchical syntactic structures defined in the study. The results suggested three-level hierarchy in phonological structure in spoken Korean: between sentences > between independent clauses > between a dependent clause and the matrix clause = any within-clause boundaries. Korean speakers paused the longest prior to starting a new sentence. They paused statistically significantly shorter between two independent clauses (e.g., coordinate clauses and adverbial clauses), and even shorter between a dependent clause (e.g., complement clauses and relative clauses) and the matrix clause. Interestingly, however, the last type of clausal boundaries, i.e., between interdependent but separate clauses, did not differ from any of the observed within-clause boundaries with respect to intonation structure marked by pauses. These results are consistent with the literature as to across-clause boundaries, but contra the traditional prediction that syntactic hierarchical structure may be mapped onto phonological structure: clausal boundaries are prosodically treated the same as within-clausal boundaries. Crosslinguistic and educational implications are discussed.