A detecting device for biochemical detections is provided. The detecting device includes a first substrate, a magnetic layer located on the first substrate, an isolation layer located on the magnetic layer, at least a first electrode located on the isolation layer, a first dielectric layer located on the first electrode, a first hydrophobic layer located on the first dielectric layer, a second substrate, at least a second electrode located on the second substrate and having a cathode and an anode, a second dielectric layer located on the second electrode and a second hydrophobic layer located on the second dielectric layer. The first electrode is zigzag-shaped, and the cathode and the anode of the second electrode are comb-shaped and interlaced with each other.