Microchips appear to offer important opportunities for modern research. Microchips based on gold magnetic nanoparticles make manipulation of biomolecules more conveniently, and has the advantage of deducing reaction time. In this study, we first achieved microchips design and fabrication through CO2 laser ablation for immunoassay, and then conjugated mouse IgG to gold magnetic nanoparticles serve as a target. Finally, HRP labeled goat anti mouse IgG binding assay and substrate reaction were performed with disposable microchips and other devices. The results indicated that the reactions carried on successfully and magnetic particles moved well in chips.