The purpose of this study was to assess budget preparation and budget utilization in World Vision Ethiopia. The study focused on budget preparation, challenges in budget implementation, budgetary monitoring and control and utilization activities undertaken during the project cycle periods. The analyst employed a cross-sectional descriptive study design and also a combination of quantitative and quantitative research approach was used to collect and analyze primary data. In order to collect primary data a survey instrument was adapted from different business literatures and by using stratified and purposive sampling techniques 122 questionnaires were distributed to management, supervisory, finance and program/project coordinator staffs of World Vision Ethiopia and only 116 questionnaires were fully filled and returned with a 95.1% response rate. The survey data were analyzed through descriptive statistics, using SPSS version 21. Budget performance reports, financial accounts, and manuals were also used to gather secondary data. The study finding revealed that the overall budget preparation and utilization practice in the organization have faced the inability of user department to utilize the allocated budgets effectively and new projects or donors having different budgeting guidelines and come with new set of rules which take time to learn, resulted underutilization of budget. So the study recommended that the organization should have a strong monitoring and control of budget by implementing variance analysis regularly and also building a strong audit system and provides training on budgeting to their staffs.