Background: PM2.5 and black carbon (BC) can be generated from cooking and from vehicle operation. Street vendors may be exposed to PM2.5 and BC due to their proximity both to roads and to cooking activities. Objectives: The objectives of this study were to evaluate the PM2.5 and BC concentrations in cooking stalls and to determine the effects of cooking activity and of types of cooking. Methods: Indoor and outdoor PM2.5 and BC concentrations, temperature, and relative humidity were measured in 32 stalls in April and May 2022. Behavioral factors such as the presence of cooking activity and types of cooking were observed. Student’s T-test was performed using the difference of indoor and outdoor PM2.5 and BC concentrations to compare the effects of cooking activity and to compare types of cooking. Results: One-hour averages of the difference in indoor and outdoor PM2.5 concentrations for cooking stalls and non-cooking stalls were 9.7±15.7 μg/m3 (n=22) and –0.5±0.4 μg/m3 (n=10), respectively. The difference in indoor and outdoor PM2.5 concentrations in cooking stalls was significantly higher than in non-cooking stalls (p<0.05). The indoor PM2.5 concentration for stalls for Chinese pancakes and teokbokki exceeded the standards for indoor air quality in South Korea (50 μg/m3). The indoor PM2.5 concentration for Korean pancake stalls exceeded the standards for outdoor air quality in South Korea (35 μg/m3 for 24 hours). Conclusions: The PM2.5 concentrations in stalls with cooking activity was significantly higher than those in stalls without cooking activity. Some stalls with certain types of foods exceeded standards for indoor and outdoor air quality in South Korea. Better management of indoor air quality in stalls with cooking activities is necessary.