Aim: The association between particulate air pollution and increased risk of type 2 diabetes (T2DM) is well established. Air pollution, a major public health concern worldwide, affects several noncommunicable diseases, including T2DM. Italy faces significant challenges in relation to both particulate air pollution and T2DM. There are no studies in Italy assessing the association between particulate matter and T2DM in a large dataset of patients with clinically diagnosed T2DM. Subject and methods: This study aims to assess the association between particulate matter (PM2.5 and PM10) and T2DM prevalence and incidence rates in Lombardy compared with the rest of Italy from 2006 to 2019. The association with years lived with disability (YLDs) was assessed using data from 2006 to 2016. Data were obtained from the AMD dataset, a comprehensive outpatient longitudinal dataset, while particulate matter data were obtained from the European Environment Agency and ARPA Lombardy, the regional environmental protection agency for Lombardy. The association was assessed using mixed-effects models. Results: The mixed-effects model showed a significant positive association between particulate matter and T2DM incidence in Italy, with notable variations over time and between regions (Lombardy vs. the rest of Italy). While no significant effect of particulate matter was observed with respect to prevalence and YLD rates, a significant positive association was found between particulate matter and incidence rates for Italy, with the effect increasing over time. The opposite tendency was observed for Lombardy, with a negative association between particulate matter and incidence, and a decreases in the effect over time. Conclusion: Particulate matter pollution, specifically PM2.5 and PM10, appears to be significantly associated with T2DM incidence rates in Italy. However, the effect varies between regions, with Lombardy showing a complex relationship influenced by socioeconomic factors. This study highlights the importance of addressing air pollution as a public health priority, particularly in regions with high levels of pollution such as Lombardy, in order to reduce the risk of T2DM and its associated burden. Graphical