The current study investigated how a guidance method that segments a complex task into simpler subtasks affects adults' inquiry-based learning in a science simulation environment. In a multivariate inquiry task, participants were asked to investigate the effects of all variables in one round of inquiry. In another group, participants were guided to investigate the effect of one variable at a time. The results indicate that the guided participants conducted more systematic and comprehensive investigations and reported a lower level of cognitive load compared with the unguided participants. The current findings provide implications for designing simulation-based learning environments to facilitate learning.