This research examined the impact of dialectical thinking (DT) on perceived training outcomes in commercial leadership training using a quasi-experimental design. Study 1 found that high-DT individuals had better perceived on-site training outcomes when compared with individuals with low DTs, regardless of training methods. But there was no significant difference between low and high DTs on subsequent behavioral improvements. It was also found that self-reported training outcomes were consistent with others' observation. To further validate the on-site effect of DT, we introduced a cognitive style manipulation prior to training to increase DT levels among trainees in Study 2. Individuals following the cognitive style manipulation reported significantly better perceived training outcomes. The implications of this research for field training are discussed.