Despite extensive research of omission effect focusing on the influence of information processing and motivation, the importance of the role of fluency on omission effect remains unclear. Studies 1 and 2 demonstrate that consumers with high retrieval and processing fluency are more likely to take inaction (omission effect). By contrast, consumers with low retrieval and processing fluency are more likely to take action (commission effect). Besides, Studies 1 and 2 further demonstrate the mediating role of the incidental affect induced by fluency in the theoretical link between fluency and omission effect.