This study sets out to explore English as foreign language (EFL) and Iranian teachers' attitudes towards the implementation of MALL instruction. For that matter, a mixed-methods design, including questionnaires, structured interviews and observation were employed. A total of 87 EFL teachers participated in the questionnaire, which was the quantitative phase of the study. In addition, 10 EFL teachers were interviewed and their classes were observed for the qualitative phase of the study. The participant EFL teachers have been teaching at a number of universities and language-teaching institutions in Mazandaran. One-sample t-test was used to analyze the questionnaire data and the results suggested that the Iranian EFL teachers adopted moderately positive attitudes towards the implementation of MALL instruction, but the observation data indicated that most teachers preferred traditional ways of teaching English in the EFL context. At the same time, the interview data revealed that the implementation of MALL instruction in Iran is challenging due to a number of perceived barriers and obstacles. The most considerable perceived challenges to the implementation of MALL instruction comprise lack of online facilities and resources, lack of interaction in online instruction, and teachers’ limited knowledge of online instruction. The findings provide crucial insights into teachers’ attitudes towards integrating MALL into their EFL classroom instruction in Iran.