Microstructure　could　induce　the　stretching　and　the　folding　of　the　interface　between　different　fluids　as　well　as　the　secondary　flow,　which　highly　influences　the　fluid　mixing　in　microchannel.　Based　on　the　prior　study　on　the　fluid　mixing　in　microchannel　with　microstructures　on　one　side,　microchannels　with　microstructures　on　two　sides　were　fabricated,　and　experiments　were　conducted　on　the　fluid　mixing.　The　experimental　results　show　that,　in　comparison　to　the　microchannel　with　microstructures　on　one　side,　no　multilamellar　fluid　structure　was　generated　in　the　microchannel　with　microstructures　on　two　sides,　resulting　in　a　low　mixing　efficiency.　In　addition,　more　structures　were　designed　in　the　microchannel　with　microstructures　on　two　sides,　which　induces　high　flow　resistance　and　low　throughput.　This　study　is　of　great　help　for　the　design　of　the　efficient　mixer　and　the　application　of　the　microfluidic　technology　in　variety　of　fields　including　biomedicine,　analytical　chemistry　and　reaction.　©　2019,　Science　Press.　All　right　reserved.