Some embodiments of the disclosure provide a multi-analyte monitoring sensor, which includes a substrate, a working electrode disposed on the substrate, an enzyme sensing layer disposed on the working electrode, and a polymer membrane layer disposed on the enzyme sensing layer. In some examples, the working electrode includes a first working electrode and a second working electrode. The enzyme sensing layer includes a first analyte enzyme layer and a second analyte enzyme layer, the first analyte enzyme layer is disposed on the first working electrode and the second analyte enzyme layer is disposed on the second working electrode, the first analyte is glucose, and the second analyte is ketone. The polymer membrane layer is permeable to both the first analyte and the second analyte and covers the first analyte enzyme layer and the second analyte enzyme layer.