The paper is based on the basic principles of public sector planning, specifically financial planning and forecasting. The level of efficiency of planning and budgeting for the selected Ministry of Defence unit is evaluated on decentral planned expenditures. Evaluation of the application of individual methods of planning (including forecasting) and budgeting, led to propose of process improvement. Based on the performed analysis and comparison, it was found out that with the budgets actually spent in the evaluated period, the planning process takes place mainly on the basis of the intuitive method. Therefore, there are large deviations between the planned and real state of the MoD Unit budget. Based on qualitative analysis, it was found insufficient application of financial planning tools (as budgeting). Another identified problem is the lack of cost management tool (hereinafter only controlling) usage. Based on the results of the paper, it can be suggested that statistical methods and management tools should be used in planning, especially controlling and performance budgeting.