Purpose This study aims to assess the factors determining the adoption of Islamic mobile banking (M-banking) in Ethiopia. Design/methodology/approach The study area covers the city of Dire Dawa, Harar and Jigjiga, where the Muslim community dominates. A sample of 378 out of 400 respondents who are currently customers of different Islamic banks provide their opinion on questions developed in a Five-point Likert scale indicator. The collected data were analyzed by the least square method and with the help of SPSS version 25. Findings The result of the study revealed that the perceived ease of use (PEOU), perceived usefulness (PU), perceived advantage and trust have a positive significant impact on the adoption of Islamic M-banking. Perceived risk was found to have an insignificant impact on the adoption of Islamic mobile banking in Ethiopia. Research limitations/implications Future researchers in the realm of Islamic mobile banking can expand their investigations in several key areas. Longitudinal and cross-cultural studies could be undertaken to explore how those factors affect over time and in different cultural settings. Practical implications As a policy implication, the study recommends that banks should develop transparent communication and implement robust security measures, emphasize practical benefits, invest in user-friendly interfaces and highlight the relative advantage they provide over others. Originality/value To the best of the authors’ knowledge, this research is considered as the first attempt to examine factors that determine Ethiopian Islamic banking customers to adopt Islamic M-banking services, which was not considered in previous studies.