The utility model provides a monitoring system, including at least one camera and with camera connection's service backstage, the camera outside still is equipped with waterproof case, and the inside vacuum of waterproof case, top are provided with antifog lens, and the camera is fixed in waterproof case and the antifog lens direction of its camera lens orientation. Among this technical scheme, adopting the vacuum casting, guaranteeing that the camera is not disturbed by steam, increase its original paper life -span, the vacuum temperature variation is less simultaneously, makes its work more stable, adopts antifog lens simultaneously, avoids external fog to disturb, guarantees its stability in long -time operational environment.