Neutron-detecting scintillator and neutron ray detector

[Problem] To provide a scintillator for neutron detection with a favorable α/β ratio, high sensitivity to neutron rays, low background noise due to γ-rays, in other words, low γ-ray sensitivity, and which can be suitably used in neutron ray detectors. [Solution] The neutron-detecting scintillator is obtained from LiSrAlF 6 monocrystals containing 0.007-0.1 mole% of at least one kind of rare earth element and the neutron ray detector is characterized in being provided with said neutron-detecting scintillator and a light detector.