This study was designed to investigate the effects of inquiry chemical experiment in chemistry teaching in promoting preservice teachers’ critical thinking dispositions. A pretest and posttest experimental design with a comparison group was employed to validate the effectiveness of the proposed approach. Ten chemical experiments were selected, and 42 chemical preservice teachers aged at 19-22 voluntarily participated in the research. The California Critical Thinking Disposition Inventory (CCTDI) was used to assess the level of preservice teachers’ critical thinking skills. The CCTDI post scores of the preservice teachers in chemical inquiry experiments training had improved, which showed that the inquiry chemical experiment has certain promoter action to the preservice teachers’ critical thinking disposition. However, the preservice teachers did not achieve high levels of Critical Thinking (CT) in either the inquiry or the traditional approaches, nor did they score high or differ significantly on subscales except analyticity. The findings indicated that inquiry chemical experiment encouraged preservice teachers’ ability to think critically, demand the application of reason and evidence and incline to anticipate consequences.