A web camera device includes a web camera and a micro processing unit (MCU). The web camera is operable to capture an image of a user. The MCU is electrically connected to the web camera and includes a distance calculating module and a comparing module. The distance calculating module is operable to receive a distance between the user and the web camera based on the calculating of the image. The comparing module is operable to compare the distance with a predetermined distance range, wherein when the distance is beyond the predetermined distance range, the comparing module outputs a warning signal for alarm the user to keep a proper distance from the display. An operating method of the web camera device is disclosed herein.