Background and aims: Air pollution is one of the health problems worldwide. Previous epidemiological studies have investigated the impacts of air pollution on respiratory and cardiovascular diseases. The aim of this study was to determine the associations between air pollution levels and different health indicators among world countries.\ud Methods: This ecological study was performed in 2013 by using dataset of World Health Organization (WHO). The main variable in our study was air pollution index. The data including Maternal Mortality Rate (MMR) (per 100000 live births), Life Expectancy at birth (LE), preterm birth rate (per 1000 live births) and Non-Communicable Diseases (NCD) death rate (per 100000 populations) from 91 countries were ex...