Background: Mastery in critical thinking skills is the ultimate goal of learning in medical education. This study was conducted to determine and compare critical thinking skills of first- and last-term baccalaureate students of nursing, midwifery and occupational therapy among medical Universities of Tehran city in 2006.

  Materials and Methods: This descriptive- comparative study was performed on 426 freshman and senior students of three medical Universities of Tehran city, including Shaheed Beheshti, Tehran and Iran. The students were completed a demographic form and California Critical Thinking Skills Test (Form B) .

  Results : There was a significant difference between total critical thinking scores of the first- and last-term students of nursing and midwifery in Shaheed Beheshti and Iran Universities ((p<0.04 and P<0/03, respectively), while there was no significant difference in other groups. In addition, no significant difference was found in total critical thinking scores of students at different disciplines and Universities.