Prostate-specific antigen (PSA) is the best serum biomarker for prostate cancer, and the detection of PSA concentration can be used to assess the risk of malignancy. Given the current lack of effective treatment options for prostate cancer, early detection and intervention are particularly important. To address this, we developed a novel electronic biosensor aimed at highly sensitive detection of PSA. The core materials of this sensor consist of the receptor material, PSA-affinity peptides, and the support material, single-walled carbon nanotubes. These materials are cost-effective, can operate at room temperature, and exhibit good stability, which aids in optimizing the sensor's performance and stability. We attached the carbon nanotubes to a gold fork electrode and successfully fabricated the device by chemically linking the peptides to the carbon nanotubes. PSA was subsequently detected through the binding of PSA molecules to specific peptide sequences in standard solution. The sensor achieved a detection limit as low as 10-13 μg/μL, which is lower than that of currently used detection methods, demonstrating exceptional sensitivity. This biosensor offers advantages such as low cost, high efficiency, and strong specificity, indicating its broad application prospects in medical diagnostics, particularly in prostate cancer screening.