Economic growth is a phenomenon that increases the welfare level of both individuals and societies. In the historical process, some of the economies of different sizes have grown faster, while others have grown more slowly. The most obvious reason for the difference can be shown as the faster progress of some countries in terms of industrialization and technological progress. In this study, it is aimed to estimate the economic growth rates of OECD countries with different economic sizes by using fuzzy and multiple regression analysis. In this direction, the Gross Domestic Product (GDP) growth rate of the countries for 2020 is considered as the dependent variable, and the Covid-19 mortality rates, interest rates, tax rates and savings rates as independent variables. R program was used for analysis. In the study, economic growth rates were estimated with fuzzy and multiple linear regression methods. Considering the literature, the h value was taken as 0.01, 0.5, 0.9, respectively, and the fuzzy regression method estimates 106 were obtained. MSE, RMSE and MAE values, which are the performance criteria of the models, were used to determine the appropriate model. When the performance values of the models were compared, it was found that the values were quite close to each other. However, it was observed that the performance criterion values of the multiple linear regression model were slightly smaller.