Summary: The self‐assembly of HPC and carboxyl‐ended surfactants such as Deac was studied in the present paper. Nanoparticles with multi‐morphologies were fabricated from HPC and Deac, and their diameter and morphology can be controlled by adjusting the molar ratio of glucose units and Deac and the environmental pH value. We also demonstrated the ubiquity of fabricating multi‐morphological nanoparticles from HPC and other carboxyl‐ended surfactants by substituting PDFOA for Deac, and it was confirmed by DLS characterization that nanoparticles with multi‐morphologies were formed at pH = 0.1. Thus the proposed approach shows a considerable potential to fabricate polysaccharide‐based multi‐morphological nanoparticles from water‐soluble polysaccharides and carboxyl‐ended surfactants.