Background: Breast cancer is the most common cause of cancer death in women in developing countries, including Ethiopia. Unhealthy dietary patterns are the most important changeable risk factors for breast cancer. Healthy dietary patterns can prevent one-third of the morbidity and mortality of breast cancer. To the best of our knowledge there is no study done to examine the association between dietary patterns and breast cancer risk among Ethiopian women. Objective: To assess the relationship between dietary pattern and the risk of breast cancer among women at Felege Hiwot Comprehensive Specialized hospital (FHCSH) in Bahir Dar City, Northwest Ethiopia, 2022. Methods: Institution-based case-control study was conducted among 263 women (88 cases and 175 controls) from May 16 to July 16 2021 in FHCSH at Bahir Dar, Northwest Ethiopia. Data were collected by face to face interviewer administered using a validated questionnaire. Data were entered into the Epi data version 3.1 and exported to SPSS version 23 for further analyses. Principal component analysis was used to identify dietary patterns. Bi-variable and multivariable logistic regressions were performed and adjusted odds ratio (AOR) with its 95% confidence intervals (CI) was used to estimate the strength of association. Results: A total of 260(case=86 and control=174) participants with a response rate of 98.9 % were included in the study. About 46.5% of the participant‟s dietary pattern was unhealthy. This study also identified that aged 18-29 years old (AOR=0.11, 95% CI: 0.02-0.60), secondary educational level (AOR=6.32, 95% CI: 1.23-32.56), self-employed (AOR=0.43, 95% CI: 0.19-0.97), unhealthy dietary patterns (AOR=8.94, 95% CI: 3.66-21.82) and chest or breast radiation therapy (AOR=7.11, 95% CI: 2.68-18.86) were associated with breast cancer. Conclusion: Approximately half of the participant‟s dietary pattern was unhealthy. This study also identified that aged 18-29 years old, secondary educational level, self-employed, unhealthy dietary patterns and chest or breast radiation therapies were associated with breast cancer. We recommend that the Regional Health Bureau should provide health education for those self-employed women, secondary educational level women about breast cancer and dietary pattern. Health care providers should minimize chest or breast radiation therapy to reduce the risk of breast cancer. Keywords: Breast cancer, dietary pattern, factor analysis, case-control study