An optical measurement device inputs excitation light to an integrating sphere in which a sample is disposed, irradiates the sample with the excitation light having a predetermined beam cross-section, detects measurement light output from the integrating sphere by a photodetector, and acquires intensity data of the sample. The optical measurement device includes a storage unit in which correction data is stored and an optical characteristic calculation unit for calculating optical characteristics of the sample based on the intensity data of the sample and the correction data. The correction data is calculated based on first corrective intensity data and second corrective intensity data. The predetermined beam cross-section is covered with the first light absorbing member and covers the second light absorbing member.