Abstract: The mechanism of unconventional superconductivity, an important topic in the study of condensed matter physics, remains a mystery. Unconventional superconductivity often occurs near magnetic instabilities, therefore the elucidation of the magnetic structure and magnetic excitations of an unconventional superconductor is critical to understanding its pairing mechanism. The neutron's magnetic moment is ideally suited for detecting the magnetic properties of unconventional superconductors. In this paper we will introduce the application of various neutron scattering techniques in the study of the crystal structure, magnetic correlation and pairing symmetry of unconventional superconductors.