This study examined the way in which risk perception of fine particular matter influences behavioral intention within the larger context of outdoor recreation. Risk perceptions of fine particular matter were classified into three sub-dimensions: social-environmental risk, economic risk, and physical risk. Then, these sub-dimensions were applied to the theory of planned behavior. 345 responses were collected from recreationists throughout the Han-river region of Seoul. The results of data analysis prove that the socio-environmental and physical risks of fine particular matter positively influence attitudes and subjective norms among recreationists. This influence is also reflected in environmental perspectives but not in perceived behavioral control. On the contrary, there were no statistically significant differences among economic risk of particular matter and attitude, subjective norms, and perceived behavioral control respectively. It was also found that the attitude of outdoor recreationists, subjective norms, and the perceived behavior control of fine particular matter positively influenced behavioral intention. These findings imply that recreation participants are aware of their attitudes toward social, environmental and physical risks, but they are not fully aware in terms of the economic risk of fine particular matter.