Background: Trauma has been a major cause of morbidity and mortality all across the globe . For the improvement of delivery of efficient care to these victims, various trauma severity indices have been devised which make it possible to plan emergency care and assess need for hospitalisation and optimise hospital resources. This study was carried out to compare and evaluate Injury Severity Score(ISS) and New Injury Severity Score(NISS) as criteria for admission of trauma patients. Methods: It was a prospective observational study. The available data was analyzed to determine and compare ISS and NISS as the criteria for admission. The statistical software SPSS (version 20) was used for data analysis. Results: A total of 102 patients were studied at Trauma Centre of our hospital. Out of the total patients, 59.8% patients had their NISS scores greater than ISS which showed that NISS is slightly more sensitive and accurate than ISS. It was observed that NISS was not better in predicting hospital stay as compared to ISS. The relationship between NISS and number of hospitalisation days was not statistically significant (p value= 0.112) whereas ISS was a better predictor of hospital stay (p value=0.042) Conclusion: In this study, it was observed that majority of parameters have favored NISS whereas parameters like hospital stay have favored ISS. Hence, we concluded that NISS is a better score than ISS in many aspects and it can be preferred over ISS as one of the criteria for Hospital admission of trauma patients.