A physiological state determination device (500, 600, 700) for determining a predetermined physiological state of a subject, the physiological state determination device comprising: a brain function activation information detection unit (541, 641, 741) configured to detect brain function activation information corresponding to the physiological state; a face change information acquisition unit (542, 642, 742) configured to acquire face change information indicating a time-series change in face data of the subject; and a physiological state determination unit (545, 645, 745) configured to determine the predetermined physiological state of the subject on the basis of the brain function activation information and the face change information, characterized in that: the brain function activation information detection unit includes a specific operation detection unit (541a, 741a) configured to, when a specific operation is performed on a predetermined device by the subject or a measuring person other than the subject, determine that a brain function activation stimulus is provided to the subject and detects the brain function activation information, wherein the predetermined physiological state is a state of depression, the brain function activation information is an emotional image, the brain function activation stimulus is presentation of an emotional image, and the specific operation is an operation of inputting an image presentation command. a brain function activation information detection unit (541, 641, 741) configured to detect brain function activation information corresponding to the physiological state; a face change information acquisition unit (542, 642, 742) configured to acquire face change information indicating a time-series change in face data of the subject; and a physiological state determination unit (545, 645, 745) configured to determine the predetermined physiological state of the subject on the basis of the brain function activation information and the face change information, characterized in that: the brain function activation information detection unit includes a specific operation detection unit (541a, 741a) configured to, when a specific operation is performed on a predetermined device by the subject or a measuring person other than the subject, determine that a brain function activation stimulus is provided to the subject and detects the brain function activation information, wherein the predetermined physiological state is a state of depression, the brain function activation information is an emotional image, the brain function activation stimulus is presentation of an emotional image, and the specific operation is an operation of inputting an image presentation command. the brain function activation information detection unit includes a specific operation detection unit (541a, 741a) configured to, when a specific operation is performed on a predetermined device by the subject or a measuring person other than the subject, determine that a brain function activation stimulus is provided to the subject and detects the brain function activation information, wherein the predetermined physiological state is a state of depression, the brain function activation information is an emotional image, the brain function activation stimulus is presentation of an emotional image, and the specific operation is an operation of inputting an image presentation command.