In order to compare the properties of polyethylene glycol-polycaprolactone（PEG-PCL）with different structures, the PCL-PEG-PCL and mPEG-b-PCL copolymers are obtained by ring-opening polymerization method and characterized by FT-IR, ¹H-NMR and GPC. The curcumin-loaded nanoparticles of "mushroom" and "brush" are prepared via self-assembly method, and the properties of the two structural nanoparticles are studied. The results show that CUR is encapsulated into the nanoparticles with an amorphous state; the nanoparticles show a smooth surface with core-shell structures and good dispersibility. Influenced by the structure of the copolymer, the "mushroom" nanoparticles have a smaller average particle size of (105.71±3.20)nm, a higher drug loading and encapsulation efficiency. Since the surface of the PCL-PEG-PCL nanoparticles forms a dense PEG-layer, protein resistance studies show that the "mushroom" nanoparticles are good in vivo stability. "Brush" nanoparticles have a lower CMC date and better sustained release properties, and have a higher inhibitory effect on HepG-2 cancer cell proliferation. The study of drug-loaded nanoparticles can provide reference for drug delivery system selection and clinical application of nanoparticles with different structures.