Background: Sleep in the intensive care unit (ICU) poses unique challenges for patients, clinicians, nurses, and researchers. Patients spend long periods in bed, remain in a supine position with minimal to no activity, and are typically not exposed to significant light variation over a 24-hour period. These conditions make sleep onset and continuity problematic. In addition, patients are subject to repeated environmental disruptions that further fragment sleep. Objectives: 1. To assess the quality of sleep among hospitalized patients of wards and ICUs 2. To compare the quality of sleep among hospitalized patients of wards and ICUs 3. To associate the quality of sleep among hospitalized patients of wards and ICUs with their selected demographic variables. Materials & Methods: In this Comparative study, we have selected 60 patients (30 – ICU’s & 30 – Ward) by Non probability purposive sampling technique. The Modified Pittsburgh Sleep Quality Index was used to assess the Quality of sleep among Hospitalized patients in ICU & Ward and scores were compared. Results: Ward patients are having mean of 5 PSQI score and ICU patients are having mean 15.57 PSQI score, so the mean difference is 10.57, this difference is large and it is statistically significant difference. It was confirmed using student independent t-test. Also each domain wise ICU patients are having more PSQI score than ward patients. So, Statistical P value is P<0.001 very high significant. Statistical analysis was carried out using the Statistical Package for Social Sciences (SPSS, version 22) statistical software’s. Conclusion: Our study showed that there is a significant difference in the Quality of sleep among Hospitalized patients in ICU’s & Wards.