The banking sector is one of the largest financial institutions which are constantly innovating new services for better customer satisfaction and convenience. Information technology is used in Banks today in all its process, starting from information sharing among different units up to the delivery of banking services to customers electronically. Among the different technologies which have been adopted in banks to deliver banking services to their customers’ mobile technology is the popular one. Mobile-Banking is the use of mobile terminals such as cell phones and personal digital assistants to access banking networks via the wireless application protocol. It is true a traditional banking has grown steadily over the years, in terms of technological-based financial services/products, the Ethiopian banking sector did not fully benefit from ICT in general and Mobile banking in particular. The main purpose of this study was to assess the factors affecting mobile banking users in the case of Abyssinia Bank Chacha branch by using the extended unified theory acceptance and use of technology model. The scope of the study was bank of Abyssinia Chacha branch. The researcher were used both primary (structured questionnaire) and secondary source (from related works of literature) of data. For this study, mixed research approach has been employed with explanatory research design. Convenience sampling techniques, correlation analysis and multiple regression models were used to assess the relationship and to identify the effect of explanatory variables on factors affecting mobile banking users. The data collected was analyzed by using SPSS 21. The findings of the analysis revealed that all the variables were positively correlated with Mobile banking users. The findings of study indicated facilitating function, hedonic motivation, trust and habit has a significant and positive impact on mobile banking usage while, social influence was with negative and insignificant values. The study recommended Abyssinia bank had to develop database and software that speed up usage of mobile banking.