This study examined the effects of tasks, with varying levels of complexity, i.e. simple, + complex and ++ complex tasks on EFL learners' oral production in a multimedia task-based language teaching environment. 57 EFL adult learners carried out a total of 12 tasks, in sets of four tasks within three different themes and different levels of complexity. During the 16 weeks of the study, the students performed three oral test tasks that were assessed in terms of accuracy, fluency and complexity, using eight different measures. This study found that scaffolding learners in performing tasks with increasing levels of complexity in a multimedia task-based language teaching/learning context, results in improved second language oral production, particularly in terms of accuracy, fluency and complexity.