Trust is a risky social decision because betrayal may occur. It’s not clear how individual differences in social risk-seeking propensity modulate brain processes of trusting strangers. We examined event-related potentials and time-frequency power to investigate this question while 40 participants played the one-shot trust game. Twenty high social risk-seekers (HSR) and 20 low social risk-seekers (LSR) made trusting or distrusting decisions regarding unknown trustees while their electroencephalogram activity was recorded. At the decision-making stage, HSR participants exhibited a larger N2 and increased β power following distrusting decisions than trusting decisions, suggesting greater cognitive control exerted to distrust. By contrast, no such N2 and β differences were found for LSR participants. At the outcome evaluation stage, LSR participants exhibited a more negative-going difference wave between loss feedback-related negativity (FRN) and gain FRN (dFRN) and increased θ power (following losses compared to gains) than did HSR participants, indicating enhanced risk sensitivity of LSR people. Our findings provide insights into the mechanism by which social risk-taking facilitates trusting strangers. The results also shed light on the temporal course of brain activity involved in trust decision-making and outcome evaluation, as well as how individual differences modulate brain dynamics of trusting strangers.