Owl feathers have been investigated for silent flight characteristics.In order to establish the feasibility of bionic application of the owls special feathers with hierarchical branches,we present the study on the morphological and mechanical characterization of branched rami at all levels of the long-eared owl primary feather.Morphological feature of the owls primary feather was obtained from the optical microscope and scanning electron microscope images firstly,as seen in Fig.1.And dimensions of all the branches were determined.Then mechanical characterization of the feather rachis and barb specimens was carried out based on the Instron 3345 single column material testing system(Fig.2),and barbule specimens on a developed micro-tensile tester(Fig.3).