An endoscope system has an insertion portion, a forward observation window configured to acquire a forward-field-of-view image, a lateral observation window configured to acquire a lateral-field-of-view image, an image pickup device and a video processor. A positional displacement correcting portion of the video processor detects a positional relationship between a portion where the forward-field-of-view image is formed and a portion where the lateral-field-of-view image is formed, on the image pickup device, and generates displacement amount data. A boundary correcting portion generates an image signal in which the forward-field-of-view image and the lateral-field-of-view image are arranged with an image center point provided in the portion and an image center point provided in the portion caused to correspond to each other, based on the displacement amount data.