Introduction: The essential goal of nursing education programs is preparing of the skilled nurses to provide comprehensive care . The investigation of critical thinking skills can be used as a basic critera for evaluating of these programs. The goal of the study was to determine levels of critical thinking skills of students enrolled in a 4 years program at nursing college in Yasouj.

  Methods: We used a descriptive and cross- sectional method for this study. A simple and non probability sample of 72 students from all 4 years of the under graduate program completed a background/demographic questionnaire and the California Critical Thinking Skills Test (form B) in 2005. The CCTST (form B) produces five cognitive subscales scores, which are: analysis, evaluation, inference, deductive reasoning, and inductive reasoning. The reliability and validity of the test were established in the several previous studies. The data were analyzed by SPSS. Both descriptive statistics and inferential statistical tests were used. Descriptive statistics include the calculations of means, standard deviations, modes, minimum and maximum scores. We used the inferential statistical tests include kruskal-wallis, t-test and regression analysis.

  Results : The mean score achieved by all participants for The CCTST was 29.82% ± 9.2. The participants scores were the highest in the inductive reasoning and the analysis subscales. Linear regression analysis revealed an inverse relationship between the average of scores of passed units and total test scores of each student ( = -.246). Also this analysis showed a positive relationship between age and total test scores( = .32). There was no statistically significant difference level of critical thinking skills between males and females.

  Conclusion: Our findings indicate an inadequate level of critical thinking skills among students examined in the present study. This study showed that there was no significant difference in the critical thinking scores of the students between males and females. In this study, it was characterized that age had a significant effect on scores of the CCTST as with increasing of age scores of the CCTST. With considering the result of this study, researchers emphasis on developing techniques and designing learning experiences. The development of students’ critical-thinking abilities in the clinical field are essential in nursing educational programs.