Maintaining air quality within building spaces is a challenge under the increased pollutants resources. The optimization of the courtyard building layout toward natural ventilation has emerged as a critical factor in shaping air quality conditions. This study delves into the assessment of outdoor air quality infiltration within a dual courtyard typology characterized by varying proportions and orientations for both the connecting link and openings. To comprehensively analyse air quality within these integrated courtyards, a combination of on-site particle dispersion measurements and flow pattern simulations were employed. The outcomes of this investigation highlight the pronounced impact of atmospheric conditions, particularly wind direction, on the performance of courtyard configurations. The results revealed that dual courtyard provide an approach to address the geometric conflict between thermal comfort and air quality optimization. Even in circumstances with limited flow velocity, the direct connection between courtyards deepens the upward recirculating flow into the courtyard cavity at the activity level. The optimal air quality is attained by planning each courtyard’s upper-level intake and outflow openings, as it provides an evacuation flow out of court cavity and decline the PNC than outside surrounding conditions.