A object change detection system characterized by comprising: object detection means for acquiring image data, including an image around a host vehicle, from a camera and detecting an object from the acquired image data; information acquisition means for acquiring, by using predetermined feature quantities, a feature quantity distribution that indicates information of the object detected by the object detection means, wherein the predetermined feature quantities include at least one of luminance of an image, an edge of an image, and a color of an image; normalization means for acquiring a probability distribution corresponding to the feature quantity distribution by normalizing the feature quantity distribution acquired by the information acquisition means; information storage means for storing the probability distribution acquired by the normalization means; change information acquisition means for acquiring a difference between the probability distribution of the predetermined period of time before and the current probability distribution as change information of the object by using the probability distributions stored by the information accumulation means; change information storage means for storing the change information acquired by the change information acquisition means; and object change detection means for detecting a change in the object, wherein the object change detection means calculates a cosine similarity between a vector of plural change information items stored by the change information storage means and a vector of a plurality of ones, and detects a change in the object when the cosine similarity is smaller than a predetermined threshold. object detection means for acquiring image data, including an image around a host vehicle, from a camera and detecting an object from the acquired image data; information acquisition means for acquiring, by using predetermined feature quantities, a feature quantity distribution that indicates information of the object detected by the object detection means, wherein the predetermined feature quantities include at least one of luminance of an image, an edge of an image, and a color of an image; normalization means for acquiring a probability distribution corresponding to the feature quantity distribution by normalizing the feature quantity distribution acquired by the information acquisition means; information storage means for storing the probability distribution acquired by the normalization means; change information acquisition means for acquiring a difference between the probability distribution of the predetermined period of time before and the current probability distribution as change information of the object by using the probability distributions stored by the information accumulation means; change information storage means for storing the change information acquired by the change information acquisition means; and object change detection means for detecting a change in the object, wherein the object change detection means calculates a cosine similarity between a vector of plural change information items stored by the change information storage means and a vector of a plurality of ones, and detects a change in the object when the cosine similarity is smaller than a predetermined threshold.