DEVELOPMENT AND VALIDATION OF ZOOM FATIGUE SCALE Abstract Fatigue is a contributing factor that affects the well-being and performance of the teachers. The purpose of this study was to develop and validate an instrument that can measure the Zoom fatigue of the teachers in conducting online classes and attending webinars and videoconferences. The researcher used the mixed method following the Sequential Exploratory Design in the study. For the qualitative part, statements were developed based on the responses of six teachers who joined the Focus Group Discussion (FGD) focused on their experiences related to videoconferencing during the pandemic. The researcher analyzed and coded the responses and formulated a 46-item instrument Zoom Fatigue model. For the quantitative part, the initial 46-item draft was administered to 20 teachers to determine the suitability and understandability of the items. The 45-item instrument was also administered to 235 teachers. Results were subjected to KMO and Barlett's tests to determine the adequacy and suitability of the items. For reliability test, a Cronbach alpha was also administered followed by the Principal Axis method with Varimax in which 42 items were considered to be reliable. The 42-item ZFS was administered to 20 teachers for the implementation of the instrument. Results revealed that teachers have a higher level of Zoom fatigue in terms of general fatigue which includes the physical, mental, and emotional aspects of individuals using videoconferencing tools. Based on the findings, the researcher crafted the guidelines for videoconferencing that can be used by the school and higher institutions to improve the delivery of Online Distance Learning in their respective school. Keywords: Zoom fatigue, development, validation, videoconferencing, online classes.