Cancer incidence and mortality are rapidly growing worldwide, and Breast Cancer is one of the leading causes of death among women in Malaysia. Social support is an important aspect of the Quality of Life (QoL) as it affects the psychological well-being and health of the patients. The aim of this study is to assess the quality of life and relationship of QoL with social support among female patients with diagnosed Breast Cancer. This is a cross-sectional study involving 259 female patients with diagnosed Breast Cancer from the outpatient unit of the National Cancer Institute, Malaysia. The European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ-C30) and its breast-specific module (QLQ-BR23) measured QoL and social support by using Perceived Social Support (MPSS) questionnaires. The data was analysed using SPSS version 25.0. The result of this study found that women with Breast Cancer in Malaysia had an excellent global quality of life in which they were able to achieve the highest score in their role and physical function. The result also showed a high rate of social support especially supports from family. There was a positive relationship between QoL and social support (rs: 0.25) generally with a p-value less than 0.05. Therefore, effective measures need to be taken and implemented concerning improving the QoL of Breast Cancer patients.