Abstarct: Economic growth in each country is considered an indicator of its progress and it is of particular importance in the economy. As a result, the study of the factors affecting it for each country's economy is considered as one of the important variables. In this research, we study the fluctuations of exchange rate, oil price and government expenditures on the economic growth of Iran baxsed on the time series data of 1995-2018. Initially, the fluctuation of exchange rate and oil prices and government expenditures were estimated using the GARCH models, Then, the interrelationships of the model variables using the self-evaluation model were investigated and further, long-term relationships between variables were also extracted using the VECM model. The results show that in the long run the fluctuations of the exchange rate and government expenditures have a negative effection economic growth and oil prices, has a positive effection economic growth.