Introduction: Surgical site infection is an infection of an incision, organ or space where a surgical procedure has been done. The definition for surgical site infection given Centre for Disease Control and Prevention (CDC) as a surgical procedure related infection that occurs at or near a surgical incision within 30 days of surgery or within 90 days of a prosthetic implant. Aims: To investigate incidence, root causes and outcomes of surgical site infections following Orthopaedic surgery in a tertiary care centre. Material and methods: The present study was a Prospective cohort study. This Study was conducted from February 2021 to November 2022 at Department of Orthopaedics, Rajendra institute of Medical Sciences, Ranchi, Jharkhand. Total 275 patients were included in this study. Result: In our study out of 275,45 patients had surgical site infections(16.5%),3 superficial infections(1.1%),42 deep infections(15.4%). Associated risk factors were found to be an increased age, comorbidity of the patient, longer duration of surgery. The most common pathogen were Staphylococcus(55.5%), Klebsiella(28.1%), Streptococcus(6.2%), Ecoli. Sensitive antibiotic to the pathogens were Amikacin, Ciprofloxacin, Meropenem, Piperacillin. Conclusion: Surgical site infections incidence rate was revealed to be higher than acceptable international ranges due to poor set up of hospital ward, lack of equipment and materials needed to maintain strict asepsis, poor hygiene of patients increasing SSI and overwhelmed emergency services due to population burden. However, multi drug resistance was seen in half of the isolates leaving clinicians with few choices of drugs for the treatment of patients with SSI. Periodic surveillance of bacteria and antibiotic susceptibility coupled with the implementation of strict protocol for antibiotic administration and operative room regulations are important to minimise the burden of SSI with resistant bacteria pathogen.