The purpose of the current study was to find out the role of task types with different task complexity in complexity, accuracy, and fluency (CAF) of speaking performance in elementary, intermediate, and advanced EFL learners. In order to achieve the above-mentioned goal, 60 participants were randomly selected from 90 composing 21 elementary, 20 intermediate, and 19 advanced participants through Oxford Placement Test. The selected participants were asked to perform different task types (i.e. personal information exchange, narrative, and decision-making) and learners’ speaking CAF was measured and analyzed. These three tasks were chosen because they vary the importance of background knowledge and general familiarity. The sampled participants were asked to perform the prepared tasks in different task complexities (low, mid, and high) and their oral CAF was measured and analyzed. To measure CAF, percentage of error-free C-units for accuracy, clauses per C-units for grammatical complexity, type-token ratio (TTR) for lexical complexity, the number of tokens (words)/total task time (per minutes) for fluency were used. The results of mixed between-within subjects analysis of variance indicated that task types were significant factors on CAF. Furthermore, the results showed that proficiency level was statistically significant on CAF as well. The findings of this study provide pedagogical implications and recommendations for language teachers, material developers, and language assessors.