Fine particulate matter (PM _2.5 ) poses severe threats to early childhood development through neurotoxic, respiratory, and immunological pathways. Developing effective public health interventions requires a deep understanding of caregiver perceptions and protective behaviors. This cross-sectional study assessed caregivers’ knowledge, attitudes, and practices (KAP) regarding PM _2.5 exposure among children in Chiang Mai, Thailand.

Caregivers were recruited at Child Development Centers during child drop-off or pick-up, with interviews scheduled at their homes or the centers. Structured questionnaires were administered to caregivers to evaluate KAP levels and identify socioeconomic predictors of protective behaviors.

Caregivers exhibited moderate knowledge (mean 10.44 ± 3.80 out of 22) and generally positive attitudes (30.74 ± 3.57 out of 40) toward PM _2.5 protection. Although 97.0% recognized the health risks to children, critical technical gaps were identified: only 41.8% understood that standard surgical masks are insufficient for PM _2.5 , and only 9.7% could correctly interpret Air Quality Index (AQI) levels. Protective practices were inconsistent (17.33 ± 5.22 out of 32), characterized by low air purifier ownership (15.3%) and infrequent use of monitoring applications (28.2%). A significant socioeconomic gradient emerged, with higher education and income serving as robust predictors of preventive practices (adjusted R ² = 0.217). Correlations between knowledge, attitudes, and practices were weakly positive (r = 0.09 to 0.26), and 81.3% of caregivers reported feelings of hopelessness regarding pollution control.

An apparent discrepancy between caregivers’ knowledge and protective practices was observed in Chiang Mai. Although high levels of concern are present, they do not always translate into effective protective actions, which may be influenced by technical misconceptions and socioeconomic barriers. Efforts focused on targeted education and subsidized protective measures could help mitigate the health burden of PM _2.5 on vulnerable pediatric populations.