The wetting characteristics of hyperbranched polyesters (HBP) added cyclic olefin copolymer (COC) melt in microchannels of anodized alumina oxide (AAO) template were studied. The wetting displacements in microchannels were measured by scanning electronic microscopy (SEM). Compared with pure COC matrix, the composite flowed much longer in the microchannels under normal molding conditions. This may be attributed to the spherical shape of the HBP molecules. The flow study was extended by applying a series of high frequency vibration on the AAO template. Results show that vibration can enhance the wetting of the composite melts if phase separation does not occur. This paper provides useful information for micromolding based microfabrication, especially additives and vibration assisted micromolding. POLYM. ENG. SCI., 2012. (C) 2011 Society of Plastics Engineers