Abstract: One of the significant considerations of government’s economic policies is the effect of these policies on quality of income distribution. In present study, the changing trend of Gini coefficient in Iran and related affective factors from 1996-2013 was examined in a logarithmic model. The impact of factors such as inflation, unemployment, Gross Domestic Product (GDP), exchange rate and targeted subsidies on dependent variable (Gini coefficient) by Eviews Software. Then the Reliability test, Integration test, Engle and Granger test, Autocorrelation test and Variance Heteroscedasticity test were conducted and it was found that all dummy independent variables introduced in this study have significant effect on the dependent variable. The independent variables of inflation, unemployment and exchange rate as well as the dummy variable of targeted subsides have positive and variable impact on independent variables GDP and negative impact on the increase in the Gini coefficient.