Introduction <p>Breast cancer in India accounts for 178361 of all cancers (Globocan 2020 report). Treatment causes financial, social, and psychological stress, impacting patients’ quality of life (QoL). Multiple studies have reported QoL among survivors, however few studies focused on patients undergoing treatment in India. Hence, the present study aimed to measure the QoL and its influencing factors associated with breast cancer undergoing various treatments in the oncology department of a tertiary care hospital in India.</p> Methods <p>A hospital-based cross-sectional study (Nov 2022 - Jan 2023) used a semi-structured questionnaire on participants’ sociodemographic and clinical characteristics. The validated Marathi and English EORTC QLQ-C30 and BR23 assessed QoL. Participants were selected using convenience sampling.</p> Results <p>A total of 285 patients agreed to participate with a mean age of 54.2 ± 12.2 years and the mean score of Global Health Status (GHS)/QoL was 54.4 ± 19.6. Patients who received radiation had more pain (<i>p</i> &lt; 0.001), insomnia (<i>p</i> &lt; 0.001), and diarrhoea (<i>p</i> = 0.005), whereas, those who received chemotherapy had higher scores in constipation (<i>p</i> &lt; 0.001) and loss of appetite (<i>p</i> = 0.001). Co-morbidities were significantly associated with breast cancer-specific symptoms scales – upset by hair loss (<i>p</i> = 0.025), arm symptoms (<i>p</i> = 0.026), and breast symptoms (<i>p</i> = 0.013).</p> Conclusion <p>Education, occupation, hours of sleep, financial issues, and type of surgery were linked to the patient’s QoL. Therefore, these patients require additional attention and support services, including effective pain management and interventions to enhance sleep quality, to further enhance their QoL. Longitudinal studies incorporating detailed clinical and psychosocial variables are needed to understand the determinants of QoL.</p>