The purpose of this study was to investigate whether and to what extent the intelligibility of Korean EFL learners' speech at the text level is affected by their English proficiency, text type, and text length. Various speech materials produced by native English speakers and two Korean EFL speaker groups (high vs. low proficiency) were presented to native English listeners and two Korean EFL listener groups, respectively, for comparison of intelligibility scores. The results showed that the listeners' overall proficiency played the most critical role in determining the level of speech intelligibility for all speaker groups, regardless of the type and length of speech materials. The speakers' proficiency level in terms of pronunciation, however, had no significant effect. As for the text type, dialogue texts were consistently more intelligible than monologues to all listener groups while the effect of text length varied depending on the text type. These results suggest that L2 learners' speech intelligibility needs to be examined within the context of natural L2 text beyond word- and sentence-level utterances in consideration of the interaction of text-related features and other learner variables. Some pedagogical implications are also discussed.