Scattering measurements on polymer solutions allow the determination of the molecular size and structure of solute molecules, as well as their molecular weight. As beam sources, visible laser light, monochromatic X-ray, and neutron are used. Angular dependence of the scattering intensity gives the particle scattering function, which is intrinsic to the molecular shape, as well as the mean-square radius of gyration as a measure of the molecular dimension. The molecular weight dependence of the mean-square radius is also used to determine molecular parameters, such as the stiffness parameter or the branching degree of the chain. Intrinsic viscosity and hydrodynamic radius are also used to determine these parameters. In this chapter, experimental techniques and data analyses of these measurements are described.