This study was conducted to develop and validate a tool for measuring the effectiveness of a teaching practicum for domestic pre-service elementary teachers. For this purpose, the researchers collected data from a total of 537 fourth-year students at 10 universities of education across the country. First, exploratory factor analysis (EFA) was performed on the primary data collected (N = 285). As a result, the teaching practicum effectiveness measurement scale consisted of 25 items with 5 factors (curriculum analysis and class design, student development support and guidance, class reflection and critique, interaction with students, and class atmosphere and class operation). Confirmation factor analysis (CFA) was then performed on the secondary data collected (N = 252). As a result, the model fit of the final model was confirmed. Also, the reliability of the final scale was verified as “good” (Cronbach s α = .959). In addition, criterion validity was also ensured through the results of correlation analysis between this scale and the Pre-service Teacher Professional Competency scale, the Elementary Teacher Job Competency scale, and the Teacher Development Diagnostic Tool. The scale developed through this study and confirmed to be reliable and valid can be an easy and efficient tool to measure the effectiveness of pre-service teachers teaching practicums. Finally, the significance and limitations of this study are discussed.