Dynamic and on-site analysis of serum from human blood is crucial, however,state-of-the-art blood-assaymethods can only collect single or discrete data of physiological analytes;t hus,t he online reports of the dynamic fluctuation of key analytes remains ag reat challenge.H ere,w ep ropose anovel separation-sensing membrane by constructing aheterogeneous-nanostructured architecture,w herein as urface nanoporous layer continuously extracts serum, while the biosensing nanochannels underneath dynamically recognise biotargets, therebya chieving ac ontinuous testing of vital clinical indices as blood is drawn. By precisely controlling the pore structure and nanoshape of biosensing crystals,this membrane achieved accurate and online glucose and lactate monitoring in patients with avariety of medical conditions within 1min, which is one order of magnitude faster than state-of-the-art techniques. Moreover,v arious kinds of bio-recognisers can be introduced into this membrane to accurately detect glutamate,t ransaminase,and cancer biomarkers.