Foreign trade she one of the most important economic sectors in all countries of the world through its positive contribution to increasing economic growth rates and national income. Achieving structural transformations in many economies of different countries by providing consumer and production goods. As well as considering it as a measure by which one can know the degree of trade openness towards the outside world of any country in the world. The research relied on studying (public spending, gross domestic product, foreign direct investment and exchange rates) and analyzing them in order to estimate that relationship.
Research amid to describe the effect of some macroeconomic variables on Iran's foreign trade in the long and short term through the use of modern economic measurement methods and estimation of that relationship during the research period (1990-2019). And after studying the static time series of the data of the variables used by using the co-integration method and relying on the time-delayed gaps regression model ARDL. The research concluded that there is a short-term relationship between the dependent variable and the independent variables, and the existence of a long-term relationship. Through results that appeared show that the sign is negative between foreign trade and variable public spending but not significance at the level of (5%). With the presence of a positive relationship between the domestic product and foreign trade and it is significant at the level of significance (5%). And that any increase in the domestic product the total by (1%) leads to an increase of (0.774%) in foreign trade. With the presence of a positive relationship between foreign trade and foreign direct investment, and that any increase in foreign direct investment by (1%) leads to an increase of (0.128%) in foreign trade. As well as the existence of the inverse relationship between exchange rates and foreign trade, which is not significant at the level of significance (5%). Recommended search paying attention to foreign trade, diversifying production and export sources, encouraging a policy of protection for national production through imposing customs taxes on imported goods, supporting local production sectors, adopting an exchange rate policy that helps increase foreign trade, the need to reform the banking system, including the industrial, agricultural and service sectors.