The annual and intraseasonal variability of near-ground daytime mixing ratios of gaseous pollutants (O3 , NO, NO2 , CO, and benzene) and aerosols (PM10 and PM2.5 ) measured at the A.M. Obukhov Institute of Atmospheric Physics of the Russian Academy of Sciences observation site in the center of Moscow in 2018–2023 is analyzed. The primary gas species (NO, NO2 , CO, and benzene) and PM2.5 show a unimodal seasonal cycle with a maximum in winter and a minimum in summer months, reflecting a combined influence of extratropical tropospheric features and local meteorology. A distinct summertime ozone maximum provides evidence for the strong input from its photochemical source, which is presumably attributed to the upper part of the urban mixing layer. The relative contribution of Moscow emissions to the observed pollutant levels during the cold (warm) season is estimated to be approximately 56% (42%) for CO and 64% (67%) for NOx, 70% (59%) for PM2.5 , and 78% (77%) for PM10 , with the remaining part beingdue to advection of chemically aged air from upwind pollutant sources on a wide range of spatial scales. The number of synoptic-scale episodes (N) with the enhanced PM2.5 and CO levels decreases exponentially with episode duration (τ, days) as N(τ) ~ e–λ∙τ where the rate of decrease (λ) is 0.66 (0.83) for the cold (warm) season.