Metacognitive monitoring and control play important roles in children's thinking, development, and problem-solving. Adult feedback also contributes to the development of children's metacognitive skills. This study aimed to explore the influence of teachers' calibration and performance feedback on the metacognitive monitoring and control of preschool children. Forty-seven children aged 4--6 years were randomly divided into two experimental groups and one control group. All three groups of children participated in a 15-minute jigsaw puzzle activity twice a day for nine days, with one experimental group receiving calibration feedback, the other receiving performance feedback, and the control group receiving no feedback. The results show that both calibration and performance feedback have a certain influence on preschoolers' metacognitive monitoring and control, as observed through a comparison between the pre-test and the post-test. Teacher feedback affects children's metacognitive performance and improves fluency in cognitive processing. At the same time, adults should pay more attention to the entire process of children's cognitive learning rather than focusing only on the results of their learning.