This study examined the factors contributing to perceptions of second language fluency and foreign accents by randomly selecting speech samples from the Spontaneous Chinese Learner Speech Corpus for perceptual ratings. Eight rating questions that reflected the oral proficiency of fluency, nativeness, accentedness, disfluencies, pronunciation, grammar, vocabulary, and comprehensibility were evaluated. The correlation analysis revealed that the fluency rating was correlated with disfluencies and vocabulary and accentedness correlated with nativeness and pronunciation. The principal component analysis showed that all the rating variables contributed similar weights to the first principal component (PC1), which represents the general impression of oral proficiency. The PC2 classified the rating variables into two categories. One group consisted of the knowledge factors of fluency, disfluency, grammar, vocabulary, and comprehensibility, whereas the other group included the sound-related factors of nativeness, accentedness, and pronunciation. The PC2 was mainly composed of nativeness and accentedness. The PC3 stood for the characteristics of oral fluency. Further multiple regression analysis showed that disfluencies and vocabulary have a substantial causal effect on fluency, whereas nativeness has a substantial effect on accent. The results have implications for the relationship between speech planning and fluency based on the Levelt speech production model.