Background: Human papillomavirus is a common pathogen that infects the skin and mucosal epithelium, is transmitted sexually; causes condylomas or squamous cell carcinomas. Two (16 and 18) of the 150 HPV serotypes are oncogenic types. Studies have been done on the infection by oncogenic human papillomavirus 16/18 and associated factors are found to be very limited in Ethiopia. Objective: This study aimed to assess the prevalence of oncogenic human papillomavirus infection (HPV 16/18) and associated factors among women. Methods: An institutional-based cross-sectional study was conducted among 337 women screened for cervical cancer in two hospitals in East Gojjam Zone from February to April 2021 G.C. Four BSc-qualified nurses who worked in the chosen hospitals collected the data using pretested questionnaire and an HPV test (OncoE6TM Cervical Test) specific to HPV16/18 in cervical swabs. Descriptive analysis was performed to determine the prevalence and a multivariate logistic regression model was used to identify the associated factors of HPV16/18 infection. Finally, statistical significance was declared at P < 0.05.Results: The prevalence of HPV infection was 14.2% (95% CI: 10.7% -18.1%). The mean age of the respondents was 36.7±9.1 years. Women with the age group of 55-65 years (AOR = 7.91, 95% CI: 1.95-32.09), early initiation of sexual intercourse (AOR = 5.36, 95% CI: 1.58-18.13), history of sexually transmitted infection (STI) (AOR = 3.52, 95% CI: 1.27-9.72), human immunodeficiency virus (HIV) positive status (AOR = 6.8, 95% CI: 1.99-23.54), and number of lifetime sexual partners (AOR = 4.37, 95% CI: 1.15-17.3) were important independent factors associated with the presence of oncogenic HPV infection. Conclusion and Recommendation: We found a relatively low prevalence of high-risk HPV infection. Age, early initiation of sexual intercourse at less than 18 years, STI of women, being HIV seropositive, and a number of sexual partners were important factors for high-risk HPV infection. Women aged > 46 years, women with early initiation of sex, a history of STI, being HIV positive, and a history of multiple sexual partners should be encouraged to be screened and vaccinated for HPV infection. Wider-ranging studies are also needed in HPV-infected women in association with the cervical lesion.