This study, an extended study of Chen and Chung (2008), investigates the difficulties encountered by Taiwanese learners in English speech timing patterns and identifies critical variables that affect native listeners’ perceptions of foreign accents. A total of 30 Taiwanese learners and 10 native speakers of American English were requested to read an article. Six variables—syllable duration, vowel reduction, pause duration, linking, consonant cluster simplification, and speech rate—were acoustically analyzed in five sentences. Ten English listeners were recruited to rate these speech samples. The results of this study showed that the Taiwanese learners displayed very different speech patterns according to the six acoustic variables from those of native English speakers. The perceptual ratings of the six individual variables exhibited a very strong positive correlation with the overall ratings, suggesting that timing patterns were a more holistic impression rather than a discrete component. Speech rate was the primary predictor determining native listeners’ perception of foreign accent. If this overall fluency variable was excluded, then vowel reduction and linking duration became the two most heavily weighted variables. A temporal perception model was tentatively proposed to account for the effects of timing variables on native English listeners’ judgment of foreign accents.