Strong Acoustic Streaming (AS) in a liquid can be generated near sharp-edge structures inside a microchannel. In this study, an experimental setup containing a Y-mixer and a sharp-edge patterned microchannel excited by a piezo-transducer is built. Based on visualisation and Iodide-Iodate Reactions, both macro-and micro-mixing performance are investigated. Results show that acoustic streaming allows a decrease of micromixing time from 0.3 s to 0.04 s. Meanwhile, the mixing enhancement by AS is very sensitive to the channel throughput, as the residence time becomes shorter at higher flowrates.