Forecasting of monetary policy tools, including reserve money of the Central Bank of Poland, in order to optimise economic decisions made by business entities operating on this market, becomes a basic canon of knowledge, in order to minimise a risk of undertaken economic operations – is currently the area of our investigation. The article raises a problem of forecasting the reserve money of the Central Bank of Poland on the basis of initial information received from the National Bank of Poland. The studies started with analysis and evaluation of time series of reserve money of the Central Bank in Poland. Then the analysed series were divided into two parts. Based on obtained results, the researchers performed forecasting of the first part of separated time series of reserve money of the Central Bank in Poland with the use of different methods. The above mentioned time series consists of 132 elements. Later on, the researches chose the best forecasting method and that was the basis for initial time series forecasting of reserve money of the Central Bank in Poland in mil PLN in retrospective terms during 2010-2021 for the next 2021-2022 years.