Background: Sepsis is known as a life-threatening organ dysfunction that is caused by a dysregulated host response to infection. Sepsis and septic shock carries high potential mortality rates, resulting in challenge and burden to healthcare system. Variation in the size of red blood cells is represented by RED cell distribution width. It is thought to be elevated when an excess amount of reticulocytes are released into circulation. RDW parameter is provided in the CBC report done by the automated analyzer. It is an inexpensive, routinely available, and rapidly measurable prognostic tool. Methodology- The study was carried out at the ICCU, Department of Medicine of tertiary care center, for period of 15-18 months. 65 patients fulfilling the inclusion and exclusion criteria were considered for the study. RDW value was recorded and it correlation with APACHE II score and mortality among the patients was noted. Data was entered in MS EXCEL spread sheet and analysed with the help of Open epi and spss software. Results- Mean age group of study population among non-survivor patient was 48.64 with SD of 17.26 and of survivor was 39.91 with SD of 16.64. Mean APACHE II score among Group I was 16.333 with SD of 7.711, in Group II was 21.307 with SD of 8.596 and in Group III was 21 with SD of 8.5. 30 days mortality among Group I was 1 (16%) in Group II was 22 (84.62%) and in Group III was 30 (90.91%). Conclusion- RDW value increased in patients with sepsis.