The invention provides a vertical incidence broadband polarization spectrometer for splitting an optical fiber bundle and an optical measurement system. The vertical incidence broadband polarization spectrometer comprises a light source, the optical fiber bundle, a light detector and a polarization unit, wherein the optical fiber bundle comprises an incident optical fiber sub-bundle and an emergent optical fiber sub-bundle; the incident optical fiber sub-bundle is provided with a first port group and a second port group; the emergent optical fiber sub-bundle is provided with a third port group and a fourth port group; and the second port group of the incident optical fiber sub-bundle and the third port group of the emergent optical fiber sub-bundle are on a same cross section. According to the vertical incidence broadband polarization spectrometer and the optical measurement system disclosed by the invention, by the adoption of the optical fiber bundle splitting and the addition of a polarization element, the luminous flux efficiency of the spectrometer is improved and the control capability to polarization lights is enhanced.