A recent controversy in the literature on protection behavior is whether individuals’ heightened risk perception boosts precautionary behavior toward disasters. We conducted a preliminary experiment (n=108) where risk perception and response efficacy were manipulated based on protection motivation theory (PMT). Contrary to the prediction of PMT, neither variable prompted actual preparedness behavior. In the main experiment (n=113), we examined the effects of two social factors (an informational variable and a relational variable) on preparedness behavior. Descriptive norms, defined as information about majority behavior, were manipulated as the informational variable. The possibility of exchanging stored food was manipulated as the relational variable. Descriptive norms influenced actual food storage behavior, but potential for food exchange did not. Participants’ attitude and intention to store food were not influenced by the two variables, suggesting that descriptive norms directly influence preparedness behaviors.