Breast cancer among women is gradually increasing in Bangladesh day by day. A number of breast cancer related etiological factors identified as age, reproductive factors, menarche, menopausal status, life style, hormone replacement therapy, genetics and alcohol intake. Obesity is an important factor for developing breast cancer in different countries. Obesity is one of the modifiable factors. The aim of the study was to find out the factors which might be associated with obesity among female breast cancer patients in Bangladesh. It was a case-control study conducted at the Department of Medical Oncology, National Institute of Cancer Research & Hospital (NICRH), Dhaka, Bangladesh from August 2014 to July 2015. Ninety one case and equal numbers of age matched controls were included in the study. The mean age of the case was 42.99 (±9.24) years and that of the control was 44.11±8.97 years. Majority of patients i.e. 59.3% (n=54) in case group was in pre-menopausal state where as 52.7% (n=48) of respondents in control group were in menopausal state. Increased waist to hip ratio (>0.85) was associated with increased risk of breast cancer (OR: 8.1). This was also true for increased BMI of ≥25kg/m² (OR: 4.57), increased waist circumference (OR: 3.52) and ever OCP use (OR: 2.11). However, para >3, education and moderate to heavy work were found to be protective against breast cancer (OR: <1). In clinical setting waist-to-hip ratio, body mass index (BMI) and waist circumference (WC) can be used effectively to identify women with an increased risk of breast cancer.