We have demonstrated a microchannel-based, surface-enhanced Raman spectroscopy (SERS) sensing approach for integrated microfluidic analysis developed using standard micro-fabrication technology. Our approach allows high-sensitivity SERS sensing with a comparatively low-excitation optical power intensity and large cross-sectional microchannel for biological cell analysis. Utilizing a microchannel with a cross section of 100 × 70 μm(2), we achieved a detection limit smaller than 10 nM for rhodamine 6G at an excitation power intensity of 132 W/cm(2), avoiding any possible heating effects on the sample under investigation. There is great potential for further improvement in the sensitivity of this microchannel-based SERS detection.