This study investigated sleep deprivation and academic performance on nursing students of University of Calabar. A self-structured instrument was administered to a sample of 109 students. Data was analyzed using SPSS version 20.0. Most, 55(50.5. %) of the respondents start depriving themselves of sleep immediately after resumption. On school days, most 53 (48.6%) respondents sleep for 1–3 hours on average; while 40(36.7%) respondents sleep for 4–6 hours on average. During weekends most, 69(63.3%) respondents sleep for 4-6 hours on average, however, during examinations, majority 73(67. %), sleep for 1–3 hours on average. 64(58.6%) take different substances to keep awake. More male 69(63.3%) respondents start depriving themselves of sleep immediately after resumption, as against 50(46%) female respondents. Male students have an average sleep of 5.02 hours during schools days; 5.07 hours during weekends, and 2.39 hours during examinations, while female students have an average sleep of 5.25 hours during schools days, 5.43 hours during weekends, and 4.77 hours during examinations. Male students have a lower mean (SD) hours of sleep of (4.16±.35) compared to female students mean (SD) hours of (5.15±.49). The result further showed a statistically significant relationship between sleep deprivation and academic performance, also, a statistically significant influence of sleep deprivation on academic performance of male and female nursing students. Recommendations: nursing students should be properly counseled on the importance of adequate sleep to their academic performance. They should only deprive themselves of sleep during school days and less during examination.