Curiosity has long been extolled as a seed for employee creativity. This causality is plausible when considering curiosity as a stable trait. However, curiosity can also oscillate as a transitory state, thus complicating the causal sequence between such state curiosity and creativity. To clarify the causal ordering and achieve a refined understanding of what role state curiosity plays in the creative process, we utilize a random-intercept cross-lagged panel model (RI-CLPM) to estimate the reciprocal effects between state curiosity and creativity at the within-person level. With a full longitudinal panel data across three-time points (N = 400), we find that at the within-person level, state curiosity has a positive lagged effect on creativity and creativity also shows a positive lagged effect on state curiosity. This research highlights that curiosity and creativity, in fact, mutually reinforce each other.