The aim of this paper is to forecasting the national health expenditure indicators and to examine the relationship between national health expenditure and its determinants in order to help decision makers analyze health expenditures and to set the relevant policies toward rationalizing the expenditure on health. Also, the study aims to analyze the relationship between macro and socio-economic factors as exogenous variables and health expenditures. Two methods were used in this study, forecasting health expenditures and Granger-Causality Relations. The method for forecasting is mainly based on the E-Views software in order to forecast the health expenditure from financing agencies perspective. To assess the causality between health spending and exogenous variables, the test involves estimating the simple vector auto regressions (VAR). We found that national health expenditure was estimated in 2015 to be $1.450 billion USD, growing at 7% annually, this due to expected increasing government health expenditure and household spending 5% and 7% respectively compared with 2014. It is anticipated that this will reach to more than 2000 million USD in 2020. Household spending is expected to increase whereas government health spending and nonprofit institute are expected to decrease. Chronic diseases comprise one of the most important variables which might significantly lead to increases in total health expenditures. Macroeconomics variables such as change in GDP per capita and population growth positively affect the overall total health expenditure. Other socioeconomic variables such as number under the age of 15 and above 65, numbers of physicians per 1000 population and beds per 1000, show no relationship with national health expenditures. For this, reviewing and modifying health financing from the three-main functions is needed ae well as reforming health insurance scheme. Also, prevention programs could be effective policy to control and decrease the growth on chronic diseases and improving health outcomes to restrict the growth of health care spending.