The pandemic of coronavirus disease 2019 (COVID-19), generate by a novel virus SARS-CoV-2, is rapidly spreading all over the world, generating a high number of deaths. One of the current questions in the field of environmental science is to explain the relationships determining the diffusion of COVID-19 in specific regions of countries. The research here focuses on case study of Italy, one of the countries in the World to experience a rapid increase in confirmed cases and deaths. Results suggest that diffusion of COVID-19 is very high in cities with high air pollution generating severe negative effects on public health o. In particular, results reveal that, among Italian provincial capitals, the number of infected people was higher in cities with more than 100 days per year exceeding limits set for PM10 or ozone, cities located in hinterland zones (i.e. away from the coast), cities having a low average intensity of wind speed and cities with a lower temperature. In hinterland cities (mostly those bordering large urban conurbations) with a high number of days exceeding PM10 and ozone limits, coupled with low wind speed (atmospheric stability), the average number of infected people in April 2020 more than tripled those that had less than 100 days of excessive air pollution. In fact, results show that more than 75% of infected individuals and about 81% of deaths in Italy of COVID-19 are in regions with high air pollution. This study must conclude that a long-run strategy to constrain future epidemics similar to the COVID-19, reducing the negative impact on public health has also to be designed in terms of environmental and sustainability policies and not only in terms of efficient approaches in medicine.