Prior work suggests that feeling small relative to nature (Nature-Self Size; NSS) and inclusion of nature in the self-concept (INS) are both associated with more pro-environmental attitudes. The present experiment asked whether exposure to stimuli eliciting awe—an emotion often evoked by extraordinary panoramic views of nature, characterized by subjective experience of “small self” and modulation of reliance on stored concepts—leads to increased NSS and/or INS, thereby promoting pro-environmental policy attitudes. Participants in this online experiment were randomly assigned to view photographs of extraordinary panoramic nature scenes, prosaic nature images, desirable foods, or neutral scenes before completing measures of INS, NSS, and support for environmental conservation policies. Analyses revealed that INS significantly mediated the effects of exposure to panoramic nature scenes (versus a neutral control) on pro-environmental policy attitudes; however, the same effect was observed for the prosaic nature and tasty foods images. Results suggest that exposure to awe-eliciting stimuli can promote pro-environmental attitudes via modulation of the self-concept, but this may be due to pleasant affect rather than awe per se. Future research with real-life stimuli and longitudinal designs is needed to further examine the lasting effects of awe and other emotional states on the self-concept and associated environmental attitudes.