The study concerns forecasting the number of soldiers in the Saudi Arabian army based on information obtained from the website: https://data.worldbank.org (The World Bank, 9.03.2020). The research began with a comparative analysis of the number of soldiers in the armies of Saudi Arabia and Russia. The idea for a comparative analysis of the number of armies of Saudi Arabia and the Russian Federation arises from Russian policy in the region of the Middle East countries, including the impact on world oil prices. The comparative analysis showed the similarities and differences in the dynamics of changes in the number of both armies dynamically. Subsequently, the primary time series data analysis on the number of Saudi Arabian troops was performed. The study selected methods for predicting raw data: Holt’s exponential smoothing and Klein’s model for the future. The next stage of the research was forecasting and the analysis and evaluation of the obtained forecasts. Klein’s model was the best forecasting model. The forecast of the number of soldiers in the Saudi Arabian army for 2020 is 251454, and for 2021, it has increased to 251006. The study ends with a summary and conclusions.