Chitosan nanopowder (NCTS) was prepared through ball milling. NCTS was successfully electrospun to nanofibers with the assistance of poly(lactic acid) (PLA) to prepare electrospun mats (NCTS/PLA). Scanning electron microscope images revealed that there were no chitosan particles in NCTS/PLA, indicating NCTS had been stretched to nanofibers. The effects of the electrospinning parameters (voltage, distance, and NCTS amount) on the morphology of NCTS/PLA were investigated. X-ray photoelectron spectroscopy verified the existence of chitosan in the mats. All the NCTS/PLA mats had a water contact angle higher than 130 degrees, showing good hydrophobicity. NCTS/PLA expressed good blood compatibility according to the results of coagulation time and platelet adhesion experiment. NCTS/PLA had a little longer activated partial thrombin time than PLA and more NCTS leaded longer coagulation times. No platelets aggregation and deformation appeared on NCTS/PLA mats. POLYM. COMPOS., 39:E416-E425, 2018. (c) 2017 Society of Plastics Engineers