This paper aims to identify the determinants of deposit balance of private commercial banks in Ethiopia. To achieve the research objective, the researcher used only secondary data obtained from the annual financial statement of selected private commercial banks. In this study, the dependent variable, which is deposit balance, and five independent variables, i.e. average deposit interest rate, branch expansion, credit accessibility, gross domestic product, and inflation rate, was employed. Explanatory research design and purposive sampling method was employed in this study. The researcher selects the sample banks purposively and it includes twelve of the listed banks for ten years (2009 -2018). The balanced panel data was analyzed by using descriptive, correlation and multiple regression analysis. The result of this study showed a positive and statistically significant effect between credit facilities and GDP with bank deposit balance. However inflation rate have a negative and significant effect with bank deposit balance. On the other hand, average deposit interest rate and branch expansion did not show a statistically significant effect with bank deposit balance. Finally, the study recommends that the management of the sample private commercial banks shall devote their time and efforts on variables of credit facilities, gross domestic product, and inflation rate in order to increase the banks deposit balance.