We investigate whether Confucian cultural factors (both past exposure and agreeing with its value) influence Taiwanese people’s promise-keeping and trusting decisions by priming Confucianism on Taiwanese college students. The results show that people are less likely to make promises and believe in others’ promises when primed their Confucianism background. On the other hand, people who have more past exposure to Confucianism (self-reported in a post-experimental Confucius background survey) are more likely to keep their promises if Confucianism-primed, while those who merely claim to adhere to Confucian values are not.