Abstract: This study, utilizing ERA-5 reanalysis data, investigates the spatiotemporal evolution characteristics of two types of intraseasonal oscillations (ISOs), 10–30 days (high-frequency, HF-ISO) and 30–60 days (low-frequency, LF-ISO) in mid-high latitude Eurasia during boreal summer. It also examines the influence of HF-ISO and LF-ISO on surface ozone pollution in North China, based on daily maximum 8-hour average ozone concentration data from the China National Environmental Monitoring Center. The results indicate that HF-ISO occurs more frequently and exhibits greater intensity compared to LF-ISO. HF-ISO propagates southeastward across mid-high latitude Eurasia at a constant speed by phase, while LF-ISO tends to intensify and persist over the Siberian region for an extended period before eventually propagating southward. Both ISOs exhibit a quasi-barotropic structure. Analysis of wave flux indicates that the southeast propagation of Rossby wave energy facilitates the propagation of temperature anomalies in a similar direction. As surface air temperature anomalies spread southward into North China, they affect local weather conditions. The distribution of ozone concentration anomalies suggests that two types of ISOs modulate key meteorological factors, such as precipitation, relative humidity, and total cloud cover, which in turn affect temperature anomalies and surface ozone concentrations. Owing to the slightly different geographic effects between the two ISOs, their corresponding impacts on surface ozone pollution anomalies also differ. Overall, this study highlights that both ISOs contribute to variations in surface ozone concentration, providing valuable insights for designing pollution control strategies in North China.