The World Health Organization (WHO) recently estimated that ambient air pollution causes 482,000 premature deaths within the WHO European Region. However, the significant potential health and societal costs of poor mental health in relation to air quality is not represented in the WHO report. This reflects the limited number of studies directly linking air pollution exposure to adverse mental health outcomes published to date. The aim of the study is to address the gaps of existing literature and quantify the effect of medium-term exposure of residential traffic air pollution at address level on common mental and psychiatric disorders as well as on physical health. A longitudinal mental health survey was conducted of 1,698 adults living in 1,075 households in South East London, from 2008 to 2013. High-resolution (20m x 20m) residential address level air pollution metrics were employed with the use of the established King's College London urban dispersion model. Data were analysed with the use of multilevel generalised linear models. Average air pollutant exposures across the time period of the study area were 43 μg/m3 nitrogen dioxide (NO2), 79 μg/m3nitrogen oxides (NOx), 22 μg/m3 particulate matter with aerodynamic diameter <2.5 μm (PM2.5), 23 μg/m3particulate matter with aerodynamic diameter <10 μm (PM10), and 32 μg/m3 ozone (O3). We found strong evidence for interquartile range increases in PM2.5, NO2, NOx to be associated with 18% to 38% increased odds of common mental disorders, 18% to 29% increased odds of poor physical health, and 15% to 25% of psychotic experiences based on standardised and validated questionnaires, after adjusting for large number of confounders, including individuals socioeconomic position and urban noise. These longitudinal associations were more pronounced in the subset of non-movers. The findings suggest that air pollution from road traffic in London is adversely affecting mental and psychiatric disorders and physical health.