Dissertation (MMed General Surgery)Background: Surgical site infection (SSI) is still a major cause of morbidity and mortality. This study aimed to determine the prevalence, risk factors, microbial and sensitivity configuration at Dodoma Regional Referral Hospital. Objective: To identify the incidence, risk factors, common microorganisms causing surgical site infection and antimicrobial sensitivity at Dodoma Regional Referral Hospital Methods: A prospective hospital based study was conducted at Dodoma Regional Hospital in clouding obstetrics/gynaecology, orthopaedics and general surgery adult and paediatric wards from January 2019 to May, 2019. A total of 357 newly operated inpatients were registered but 11 patients among the group lost their lives. Results: Three hundred and fifty-seven patients were followed up for the development of surgical site infection. 59 patients developed features of surgical site infection. No patient who developed SSI was reported to have died. Majority of the infections were from obstetrics and gynaecology department (6.2%), followed by Surgical department (5.9%), and finally orthopaedics department (4.5%). The predominant organism isolated was staphylococcus aureus (50%), Klebsiella (19%), Pseudomonas (12%), E. coli (12%), Proteus vulgaris 0.8% and Proteus mirabilis (3%). Conclusion: The occurrence of infection in our centre is still high and the pattern of microbes causing surgical site infection differs from one place or hospital to another while staphylococcus aureus is dominant in surgery and Klebsiella in obstetrics/gynaecology.