The purpose of this study was to test the effects of modified self-reflection notes (M-SRN) on the critical thinking abilities and selfdirected learning abilities of nursing students. The students of a theory-based adult nursing class were asked to do M-SRNs. The data was collected from 226 third year nursing students, once at the beginning of the semester and again towards the end of the semester. A paired t-test was used for data analysis. As for the results of this study, the mean score for critical thinking abilities of the nursing students increased from 3.40 to 3.66. This difference in the mean score for critical thinking abilities was statistically significant. The mean score of the self-directed learning abilities also significantly increased from 3.11 to 3.37. In conclusion, modified self-reflection notes should be considered a helpful tool for students to improve their critical thinking and self-directed learning abilities.