The invention discloses a device for preventing generation of water stain smoke, and belongs to the technical field of tobacco processing equipment. The device is particularly used for preventing water vapor stain smoke of heating and humidifying equipment. The device is preferably made of a single piece of stainless steel plate and is in bolted connection with an outlet of the heating and humidifying equipment through a bolt hole, so that a second panel is kept perpendicular in the horizontal direction, a first panel is an open hole panel, the hole diameter is preferably 3 mm, the included angle between the first panel and the second panel is 15 degrees, the lower portion is provided with an opening device such as a water collection groove, and an open hole in the tail end of the openingdevice is connected with a hose. The device is simple in structure, low in cost and small in mounting position limitation. Water vapor enters a cavity through the first panel, condensed water is formed on the second panel and collected into the water collection groove, the device is connected to a floor drain through the hose, tobacco leaves are isolated by the first panel to be prevented from being in contact with the condensed water, and the generation of the water stain smoke is prevented.