This study examines the preferred vocabulary learning strategies of Iranian upper-intermediate EFL learners. In order to identify the aforementioned group in terms of language proficiency, a TOEFL test was administered to a population of 146 undergraduate EFL students at the university of Vali-e-Asr in Rafsanjan, Iran. Those scoring above 480 were arbitrarily labeled as upper-intermediate. Subsequently a questionnaire known as VOLSI (Vocabulary Learning Strategies Inventory) was given to the same subjects to come up with their preferred vocabulary learning strategies. Finally, a stepwise multiple regression analysis revealed that 11.4% of the variance in the learners' L2 proficiency can be accounted for by three strategy categories involving "self-motivation," "word organization," and "authentic language use." In addition, an independent-samples t-test indicated no significant difference between learners' gender and their VLS choice.