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In a recent laser light-scattering study on the “globule-to-coil” transition (melting) of a single poly (N-isopropylacrylamide)(PNIPAM) linear chain in water (the solution is in the stable one-phase region at all temperatures), we observed that at the initial melting stage the ratio of the hydrodynamic radius to the radius of gyration underwent an unexpected maximum (∼ 1.61) which is even higher than (5/3) 1/2 predicted for a rigid and uniform globule, indicating a molten globule. This finding suggests that just as with a protein molecule the melting of a homopolymer globule is not an all-or-none process and the molten state is a general phenomenon for macromolecules in solution.