Nanofibers were electrospun from gelatin and chitosan at different mass ratios (gelatin/chitosan: 0/100, 25/75, 50/50, 75/25, 100/0). Atomic force microscopy (AFM) combined with scanning electron microscopy (SEM) was utilized in this study to evaluate the morphological and mechanical properties of the gelatin-chitosan nanofibers. The SEM images showed that the electrospun gelatin-chitosan nanofibers possessed more uniform morphologies than the pure gelatin or chitosan nanofibers. Moreover, AFM-HarmoniX mode was used to quantitatively assess the Denaguin-Muller-Toporov (DMT) modulus of gelatin-chitosan nanofibers. After modified by two correction factors, the DMT modulus of gelatin-chitosan nanofibers showed higher values than the pure gelatin or chitosan nanofibers, which indicated the existence of intermolecular interaction within the electrospun gelatin-chitosan nanofibers. (C) 2012 Elsevier B.V. All rights reserved.