The present mixed-methods study examined the role of learner appraisals of speech tasks in second language (L2) French fluency. Forty adult learners in a Canadian immersion program participated in the study that compared four sources of data: (1) objectively measured utterance fluency in participants' performances of three narrative tasks differing in their conceptualization and formulation demands, (2) a questionnaire on their interest, task-related anxiety, task motivation, and perceived success in task-completion, (3) an interview in which they elaborated on their perceptions of the tasks, and (4) subjective ratings of their performances by three native speakers. Findings showed the cognitive demands of tasks were associated with learners' affective responses to tasks as well as objective and subjective measures of fluency. Furthermore, task-related anxiety and perceived success in task completion were the most important affective factors associated with fluent task performance, whereas interest and task motivation were correlated with native speakers' fluency ratings. These results are discussed in terms of how task design and implementation can contribute to enhanced task motivation and performance in the classroom.