This study investigated the critical thinking dispositions and skills of senior nursing students. Study participants were students enrolled in associate (n = 137), baccalaureate (n = 102), and KN-to-BSN (n = 66) programs accredited by the Korean Ministry of Education. The California Critical Thinking Disposition Inventory (CCTDI) and California Critical Thinking Skills Test (CCTST) were used. A comparison of the CCTDI scores revealed a statistically significant difference between the students enrolled in different programs (F = 4.159, p = 0.017), as did a comparison of the CCTST scores (F = 24.205, p < 0.0001). Within the total sample (n = 305), the relationship between CCTDI and CCTST scores was significant (r = 0.305, p = 0.000). Developments in medical technology, the growing number of older adults and patients with chronic illnesses, and the demand for high-quality nursing care have led to various, increasingly complex, professional, legal, and educational issues within the nursing workplace. Therefore, nurses need creativity and critical thinking skills to make the decisions required of them in their nursing practice. In line with this, when conducting a survey of the effectiveness of nursing education, the necessity of critical thinking skills cannot be overlooked. In fact, the National League for Nursing Accrediting Commission (NLNAC) (1999) and American Association of Colleges of Nursing (AACN) (1998) require the concept of critical thinking be included as one of the core elements of curricula and that it be measured as an outcome when evaluating nursing education. In 1998, during the evaluation of colleges of nursing conducted by the South Korean Council for University Education, several universities presented the fostering of critical thinking as one of the terminal learning goals of nursing education based on the idea that critical thinking is important not only in the nursing workplace, but also in nursing education. To evaluate the effectiveness of Korea's current nursing education curriculum, focus was placed on current students in South Korea's three systems of nursing education. Each curriculum's effectiveness can be evaluated by indexing critical thinking dispositions and skills. This article intends to offer insight into the first steps necessary in reorganizing nursing education by comparing these evaluations of each of the three systems. To this end, we conducted a comparative study of the critical thinking dispositions and skills of students in 3-year associate degree (ADN), 4-year baccalaureate (BSN), and 5-year RN-to-BSN programs. The RN-to-BSN program requires students to finish a separate 2-year program after the initial 3-year ADN program.