Previous studies on the effect of planning on language production have revealed that planning does have a positive effect on language performance in terms of fluency, complexity, and accuracy. The present study was an attempt to investigate the effects of pre-task, on-line, and both pre-task and on-line planning on fluency, accuracy, and complexity of Iranian EFL learners’ written production. Forty five Iranian learners of English performed a narrative task based on a series of six pictures. The narratives, then, were coded to measure the fluency, accuracy, and complexity of the participants' production. The results of one-way ANOVA revealed that on-line planning (OLP) and pre-task plus on-line planning (PTP+OLP) had no effect on the fluency, complexity, and accuracy of the Iranian EFL learners’ written narratives. However, pre-task planning (PTP) had a significant effect on one variable of fluency (i.e. syllables per minute) but it had no effect on the complexity and accuracy of the written narratives. Findings have pedagogical implications for language teachers and syllabus designers in EFL context.