This study examined whether differences in phonological awareness were related to differences in speech comprehensibility. Seventeen adults who learned English as a foreign language (EFL) in academic settings completed 14 tests of phonological awareness that measured their explicit knowledge of English phonological structures, and three tests of phonological short term memory. The same participants also read aloud a passage and narrated picture stories. These tasks were used by 12 native speakers of English to rate the EFL speakers' comprehensibility on a 9-point scale. There was a strong positive correlation between composite phonological awareness scores and rated comprehensibility and between composite phonological awareness scores and phonological short term memory. The correlation between rated comprehensibility and phonological short term memory was not significant. A simple linear regression analysis showed that approximately 19% of the variance in rated comprehensibility scores was accounted for by composite phonological awareness scores. The study offers support to the view that phonological awareness is related to differences in speech comprehensibility and the results suggest that form-focused instruction in phonology may contribute to the comprehensibility of EFL speakers.