Novelty and appropriateness have long been considered as the two fundamental elements of creativity; however, whether these two can separately affect creativity or its related processes remains unclear. In the present study, the authors focused on psychotherapeutic insight to identify the different effects of novelty and appropriateness. Three experiments were conducted (total N = 452) using a micro-counselling dialogue (MCD) paradigm, which can induce stable and differential insights by providing different types of solutions to mental distress problems (Experiment 1) and negative descriptions (Experiment 2). Further, in Experiment 3, the authors improved the study by employing a group of high school students with test anxiety (assessed using the Test Anxiety Inventory), which was more ecological. Across the three experiments, higher insightfulness and pleasantness were induced by high novelty (experiments 1 and 2) and appropriateness (experiments 1 to 3). In Experiment 3, the effect of test anxiety was found, wherein the low-test anxiety group generated higher insightfulness compared to the high-test anxiety group, and this effect was stronger in the inappropriateness condition. The results provide evidence that novelty and appropriateness are key factors in inducing psychotherapeutic insightfulness.