Herein, we present simple integration of the microchannel and stacked carbon electrode set enabling high electrochemical current signal amplification due to redox cycling effect. The stacked electrode set consists of a substrate-bound carbon electrode and a suspended carbon nanomesh electrode (width = ∼300 nm, thickness = ∼600 nm) with a narrow electrode gap (∼4 μm) achieved using a polymerization-stop layer. A planar PDMS plate ceiling and the side walls of the carbon posts that support the carbon nanomesh enclose the electrode set and thus the sensor-integrated microchannel is completed by simple PDMS bonding process without any complex alignment process. The stacked electrode set embedded in the microchannel showed ∼1,300 times amplified current signal in chronoamperometry.