The study employed a GIS approach to analyze COVID-19 mortality cases in Iran, revealing regional variations influenced by factors like population density and socioeconomic status (11). The findings align with previous research, highlighting the role of geographical location in mortality rates within the country. Provinces such as Razavi Khorasan, West Azerbaijan, Mazandaran, Khuzestan, and Tehran showed the highest mortality rates, reflecting disparities in health outcomes (12). When examining the eastern, western, northern, southern, and central regions, Razavi Khorasan, West Azerbaijan, Mazandaran, Khuzestan, and Tehran respectively emerged as the provinces with the highest mortality rates (13). In this regard, Lai et al. identified that factors like population density and healthcare capacity contributing to mortality rate disparities globally(14). Tan et al. highlighted geographic disparities in COVID-19 cases and deaths, emphasizing local contexts, population density, racial/ethnic disparities, and healthcare access. Understanding these factors strengthens insights into the impact of geography on mortality rates (15). High mortality rates are influenced by factors beyond healthcare access, including lifestyle choices, environmental factors, and pre-existing health conditions. Identifying regional disparities is crucial for addressing health outcome inequalities and guiding public health interventions and resource allocation (16). Additionally, Furthermore, variations in environmental characteristics like temperature, precipitation, and air pollution are observed across regions due to factors such as geographical features, climate conditions, and human activities. Regions with high industrial or transportation activity may have elevated air pollutant levels, while those with high temperatures and precipitation may be more vulnerable to weather events like heat waves or flooding (17). Various demographic and environmental factors indirectly influence the transmission and fatality rate of the COVID-19 virus. An intriguing study in Iran found a positive correlation between temperature and hospitalization cases, but no direct link to COVID-19 mortality (18). Population density is a significant factor in disease spread, with high-density areas facilitating transmission due to increased proximity. A US study revealed higher COVID-19 mortality rates in regions with greater population density, older age groups, and minority populations, linked to air pollution and poverty (19). Regions with high air pollution levels may have more respiratory diseases, worsening COVID-19 outcomes. Additionally, healthcare infrastructure quality, affected by factors like population density and road connectivity, influences COVID-19 mortality rates. Moreover, limited access to healthcare resources and challenges in implementing effective public health interventions may contribute to the spread of the virus. The study's findings highlight intriguing correlations between mortality rates and environmental factors in different Iranian provinces. Provinces with smaller areas showed higher mortality rates, suggesting a role for population density in COVID-19 transmission, consistent with previous research advocating for social distancing in densely populated areas. Additionally, our analysis found that provinces like South Khorasan, Sistan-Baluchestan, Semnan, Bushehr, and Ilam had higher mortality rates with increasing average temperature, indicating a potential influence of temperature on COVID-19 severity in warmer regions. Furthermore, certain provinces, including Kohgiluyeh and Boyer-Ahmad, Ilam, Ardabil, and Kordestan, showed a stronger correlation between precipitation and COVID-19 mortality, suggesting precipitation's impact on virus transmission and severity in these areas. Our study also highlighted air pollution as a significant factor in COVID-19 mortality, particularly in central and southern regions, with the Urmia Lake region notably affected by elevated mortality rates linked to air pollution. The study confirms the link between air pollution and respiratory diseases, potentially worsening COVID-19 symptoms. Higher mortality rates in provinces with greater road density suggest transportation patterns aid virus spread. Regions with lower road density may manage virus spread better due to reduced traffic and population density. Population density and urbanization play a significant role in determining COVID-19 mortality rates. Environmental factors like NO2, O3, and population density positively correlate with COVID-19 mortality rates. Lower road density and larger land areas may enhance virus transmission management. Reduced CO2 and SO2 levels indicate improved air quality and lower mortality rates. Previous research supports air pollution, weather patterns, and population density as crucial factors in COVID-19 spread and severity. Higher air pollution levels are linked to increased COVID-19 mortality rates in regions with higher poverty and socioeconomic inequality(20). The recent study in Italy reveals a significant link between higher air pollution levels, specifically PM2.5, and increased COVID-19 mortality rates, alongside associations with population density and older demographics (21). These insights provide crucial information on the factors influencing COVID-19 transmission and severity in Iran. Policymakers and health officials can use this data to target interventions in high-risk regions and enhance healthcare infrastructure in urban areas. However, further research is needed to validate these findings and understand the intricate relationship between environmental and demographic factors in COVID-19 transmission.