The idea that language learning is facilitated or inhibited by a multitude of factors has prompted scholars in the field to investigate variables considered to be crucial in the process of second or foreign language learning. This study investigated relationships between emotional intelligence, learning style, language learning strategy use, and the L2 achievement of Iranian EFL learners. One hundred and thirty eight Iranian EFL learners participated in the study by completing three Likert-scale questionnaires: the "Emotional Quotient Inventory" (Bar-on, 1997), the "Learning Style Questionnaire" (Kolb, 1984), and the "Strategy Inventory for Language Learning" (Oxford, 1990). Also, the participants' final scores in the previous four terms were collected and their average was regarded as their L2 achievement. The results of Pearson correlation analyses revealed there was no statistically significant relationship between learning styles and L2 achievement; however, the findings indicated L2 achievement was significantly related to emotional intelligence as well as to language learning strategy use. The results of multiple regression analysis revealed that among the variables of the study, strategy use, followed by emotional intelligence, was a stronger predictor of L2 achievement. Moreover, the findings indicated that of the components of emotional intelligence, assertiveness was the best predictor of L2 achievement.