This study is based on an intervention designed to enhance early childhood teacher candidates' critical thinking abilities. The concept, elements, standards, and traits of critical thinking were integrated into the main course contents, and the effects of the intervention were examined. The results indicated that early childhood teacher candidates' dispositions toward critical thinking significantly increased after the intervention. In addition, their knowledge about critical thinking and ability to apply critical thinking in their own learning showed growth as well. Curricula implications for early childhood teacher preparation programs and instructional practices for teacher educators are discussed.