Introduction.Obesity is an independent risk factor and prognostic factor of primary breast cancer. Abundant adipose tissue would lead to an increment of blood estrogen level; thus, promoting the proliferation of cancer cells, especially those with positive estrogen receptor (ER) and progesterone receptor (PR). No study reported the association between obesity and hormone receptor characteristics of primary breast cancer in Indonesia. Method. We collected cases of primary breast cancer, which is diagnosed and undergone immunohistochemistry examination at Cipto Mangunkusumo General Hospital in 2017. The subjects divided into obese groups and non-obese groups. The ER and PR characteristics of both groups were compared Results. We collected 202 cases of primary breast cancer, with 89 cases (44%) in the obese group and 113 cases (56%) in the non-obese group. The mean body mass index (BMI) of the subjects was 24.45±4.3. Both groups were similar in terms of age, menopausal status, stage, histopathological morphology and grade. No significant association was found between obesity and ER or PR. We analyzed the correlation between BMI and the percentage of expressed hormone receptors, but no correlation found. This finding did not conform to other Western studies. The difference in the characteristics of the subjects and other hormonal factors might contribute to the outcome. Conclusion. There is no association between obesity and hormone receptor characteristics of primary breast cancer at Cipto Mangunkusumo General Hospital in 2017.