Microteaching is regarded as an effective method that allows preservice teachers to gain the experience of instructional processes and is used to improve teaching skills in an environment similar to a real classroom. Microteaching, which is utilized as a method for increasing the quality of a teacher’s education, is also used in research studies conducted within the scope of Technological Pedagogical Content Knowledge (TPCK). Accordingly, the purpose of this research is to observe changes in preservice teachers’ TPCK from their microteaching practices conducted under a conceptual TPCK framework. The participants are 52 third-year preservice teachers. An analysis was performed based on specific themes from the application, which had been developed to reveal the changes in preservice teachers’ conceptual framework of TPCK components. Content analysis was used to analyze the observation forms, self-evaluations, and transcriptions from the interviews on the self-evaluations for the effects over their procedural changes within the context of the themes. The study’s findings indicate that preservice teachers use the technological tools to attain what they had specified in their instructional plans. Also when considered in terms of the TPCK components, preservice teachers made remarkable progress.