The invention relates to a dust haze preventing energy-saving window, and belongs to the technical field of building. The dust haze preventing energy-saving window comprises a fixed sash and an opening sash, wherein the opening sash is arranged on any side edge of the upper side edge, the lower side edge, the left side edge and the right side edge of the fixed sash and is in a narrow-strip shape. The opening sash is a ventilating sash and comprises an inner window body and an outer window body, the outer window body is a glass window, the window face of the inner window body is formed by sandwiching a filtering cotton layer in a double-layer steel wire gauze, the inner window body is opened inwards, and the outer window body is opened outwards. When the outer window body of the opening sash is opened, and the inner window body of the opening sash is closed, the heat preservation performance of the energy-saving window is equivalent to that of a double-layer glass window, and while the requirement for ventilation of a room is met, it can be ensured that indoor temperature does not fluctuate substantially, which is beneficial to health of people and plants in the room and heat preservation and energy conservation of a building. The dust haze harm is effectively reduced, and dust and mosquitoes are prevented from entering the room. The ventilating performance can fully meet the requirement for ventilation of the room, the ventilation property is 300 mm/s, and therefore the ventilating effect is excellent.