The ability to detect a partner’s trustworthiness and adjust one’s own trust decisions accordingly is crucial and adaptive for maintaining cooperative relationships. Trusting a trustworthy partner maximizes mutual benefits; withholding trust from an untrustworthy partner minimizes chances of being exploited. We sought to understand how young children learn through experience and adjust their own trust behaviors when they interact with trustworthy and untrustworthy individuals. In this study, N = 96 6 to 11 year olds played 40 trials of repeated Trust Game with a trustworthy and an untrustworthy partner (20 trials each, order randomized). Results showed that although children across all age groups correctly identified the trustworthiness of their partners post-game, surprisingly, they did not trust the trustworthy partner more than chance level, nor did they show increasing differentiation between the two partners across the trials. These findings suggest a knowledge-behavior gap in children’s trust interaction with novel partners.