Background: Nurses working in shift duties, including night duties, are subject to a cumulative sleep debt, a decreased quantity and quality of sleep, and continuous sleep deprivation. Hence, nurses working in shift duties are prone to sleep disturbance. Objective: To determine and compare the quality of sleep among oncology and intensive care unit (ICU) nurses. Materials and Methods: Descriptive approach was adopted for this study. The sample comprised 126 nurses working at the units of Prince Bijay Singh Memorial (PBM) Hospital, Bikaner, Rajasthan, who were selected by purposive sampling technique. The quality of sleep was assessed by the Pittsburgh Sleep Quality Index (PSQI). Data were analyzed by using the Statistical Package for the Social Sciences (SPSS) software program, version 20.0. Results: In this study, majority of the participants (60.32%) were men. Majority of the nurses (75.40%) were working on a regular basis. The mean sleep quality scores of intensive care and oncology nurses were 3.863 ± 1.988 and 5.317 ± 1.899, respectively. The observed difference was statistically significant (t = 4.097; p < 0.001). Overall, there was poor quality of sleep in 46% of the participants. The intensive care unit (ICU) nurses are more likely to have poor quality of sleep than oncology nurses (61.90% vs. 30.16%; Χ2 = 18.15; p < 0.001). In addition, a moderate positive correlation (r = 0.6645, P = 0.0001*) was observed between the sleep quality of ICU and oncology nurses. Among the intensive care nurses and oncology nurses, there was no significant association between sociodemographic variables such as gender, age, working status, job status, and the PSQI scores. (P > 0.05). Conclusion: Intensive care nurses and oncology nurses have poor quality of sleep, which can affect their health and professional performance. The ICU nurses have poorer quality of sleep than oncology nurses. Nurse administrators and hospital administration should take initiatives to reduce the prevalence of poor sleep among these nurses.