Diagnosis of breast cancer (BC) by using sensitive and specific biomarkers is necessary. Cell-free DNA is a candidate biomarker in various cancers. Contrasting, shorted uniformed DNA released from apoptotic non-diseased cells, DNA released from malignant cells varies in size. DNA integrity is a ratio between 247 and 115bp. So, this study was designed to investigate the role of plasma ALU-247, ALU-115, and DNA integrity as possible diagnostic and prognostic markers in BC patients as compared to plasma CA15.3. The concentrations of selected parameters were determined for 40 patients with BC (2 stage I, 31 stage II, 2 stage III, and 5 stage IV) and 10 healthy volunteers by quantitative real-time PCR and ELISA. The sensitivities of ALU-247, ALU-115, and cfDI as biomarkers for BC were evaluated and compared with CA15.3. Also, disease-free survival and overall survival were estimated. For all parameters, the concentrations in patients were significantly higher than in the control group; association with tumor stage and high sensitivities was observed. The studied parameters failed to predict survival or relapse in BC patients before surgery. Plasma ALU-247, ALU-115, and DNA integrity may prove to have clinical utility in BC diagnosis. Elevated preoperative CA15.3 was shown to be directly related to tumor burden, which may improve its diagnostic capability. Those selected parameters could be effectively used together with plasma CA15.3 for BC screening at early stage. Furthermore, both ALU-247 and ALU-115 seem to be preoperative prognostic markers for BC.