The current study compares the effects of two types of pronunciation instruction (segmental- and suprasegmental-based) on the development of second-year Chinese undergraduate students' English pronunciation as against a group with no specific pronunciation (NSP) instruction. The participants were 90 university-level students in the Chinese mainland, from three intact classes. One class was taught with a segmental focus (N = 30) and the second with a suprasegmental focus (N = 31), while the third received NSP instruction (N = 29). The results showed that after an 18-week period of instruction, both the segmental and suprasegmental groups made statistically significant progress in pronunciation, as measured by comprehensibility on a sentence-reading task; however, only the suprasegmental group made statistically significant progress in comprehensibility at the spontaneous level, and it was also the only group that maintained these spontaneous gains on the delayed posttest. The positive effects of explicit pronunciation instruction in general and of suprasegmental instruction in particular account for the findings.