Introduction <p>India faces an ongoing challenge of ambient air pollution, leading to rising early deaths from non-communicable diseases. Fine particulate matter is a major environmental risk factor for cardiovascular disease, cancer, respiratory disease, and diabetes. However, a national-level time-series study linking long-term particulate exposure to premature mortality in India remains scarce.</p> Aim/objective <p>To examine trends in particulate matter exposure and premature deaths due to major non-communicable diseases in India and to assess their temporal association between 1990 and 2019.</p> Method <p>An ecological time-series study analysed global health data for trends in particulate matter exposure and premature deaths from noncommunicable diseases. Correlation and regression models examined associations, controlling for non-stationarity and autocorrelation using a socioeconomic index. Differenced and autoregressive distributed lag models were used to evaluate short- and long-term relationships.</p> Results <p>Particulate matter exposure in India exceeded guidelines throughout the study. Premature deaths from non-communicable diseases increased, primarily from cardiovascular conditions, with diabetes and cancer rising fastest. PM_2.5 exposure showed moderate correlation with early mortality (<i>r</i> = 0.475, <i>p</i> = 0.008). While immediate PM_2.5-mortality correlations were insignificant after controlling for socioeconomic factors, analysis revealed significant effects two years post-exposure, though without confirming long-term relationships.</p> Conclusion <p>Short-term particulate matter exposure did not directly explain premature mortality after accounting for socioeconomic conditions. Results show PM_2.5 exposure correlates with delayed increases in mortality. Mortality in India is influenced by demographic, socioeconomic and environmental factors. Reducing premature deaths requires both improvements in air quality and socioeconomic interventions.</p>