The structure of polyethylene oxide (PEO) was investigated by neutron scattering in both semicrystalline and liquid states. Deuterated samples were studied in addition to the protonated ones in order to avoid the large incoherent scattering of hydrogen and identify features in the pair correlation functions attributable to C-H pairs. Analysis of the deuterated sample gave additional information on the C-O and C-C pairs. The results are compared with molecular-dynamics simulations of liquid PEG.