the present study was conducted in order to investigate the impact of an integrated model of form-focused and task-based instruction on iranian efl learners vocabulary learning and retention.it also aimed to detect efl learners attitude towards the implementation of form-focused task-based vocabulary instruction in the classroom. in order to address the purposes of this study, a sample of 60 elementary efl learners of junior high schools were selected based on their performance on a proficiency test (i.e., key english test). prior to the main study, the instruments of the study (pretest, posttest and questionnaire) were piloted on 20 efl learners of the similar age and proficiency level in order to check their reliability and validity. the learners knowledge of vocabulary items were pretested at the beginning of the study.participants were divided into two groups of control and experimental and the treatments of the study were administered. the experimental group received form-focused task-based vocabulary instruction as treatments and control group received traditional and routine methods of vocabulary instruction. two posttests (immediate and delayed) were conducted immediately after the end of treatment sessions and one week later to measure learners vocabulary learning and retention. the results of two samples t-tests showed that form-focused task-based instruction had a significant impact on learners vocabulary learning and retention. it was also found that the majority of the participants had a positive attitude towards their experience of vocabulary learning through form-focused task-based instruction.
key words: form-focused instruction – task-based instruction – vocabulary learning – vocabulary recall and retention