The convergence of telecommunication and banking services in the world has created opportunities for the emergence of mobile commerce, in particular mobile money services, which provide time independence, convenience and cost saving for customers. However, its adoption by the community still needs improvement compared to its potential. The main objective of this study is to investigate determinants of adoption of telebirr mobile money service in the case of Gondar city telebirr customers. Quantitative research approach and explanatory research design was employed to examine six influencing factors namely awareness, perceived usefulness, perceived ease of use, prior technological knowledge, perceived risk and relative advantage. The researcher used convenience-sampling technique used as a sampling method to select sample respondents. 384 questionnaires were distributed to selected respondents and 318 were returned. The data has been analyzed using descriptive and inferential analysis techniques frequency, mean, correlation and multiple linear regression analysis. The result of correlation indicated all included independent variable have associate with the dependent variable. The study found that awareness, perceived usefulness, perceived ease of use, and prior technological knowledge have significant and positive impact Telebirr mobile money service adoption and perceived risk has significant and negative impact on Telebirr mobile money service adoption. However, relative advantage does not affect Telebirr mobile money service adoption significantly. The model with these influencing determinants was found to predict 61.5% of the variability of dependent variable leaving the remaining 38.5% to variables not included in this study. The researcher recommends that Ethio-Telecom should realize the effect of determinants factors, draft, and implement appropriate strategies.