The invention provides a horizontal multisource steam waste heat recovery energy-saving device, and belongs to the technical field of energy conservation and environmental friendliness. The horizontalmultisource steam waste heat recovery energy-saving device comprises a liquid inlet chamber, a heat exchange chamber, a liquid outlet chamber, row tubes, a steam isolation plate, a liquid isolation plate and the like. Inlets for waste steam and waste condensate water at different pressures and temperatures are formed according to the heat exchange gradient, so that the problem of integrated mixing and recycling of steam and the waste condensate water under different pressures is solved; the multilayer steam isolation plate is matched with the staggered separation of the row tubes, and the liquid isolation plate is used for adjusting the flow direction of liquid, so that the heat exchange efficiency is further improved; effective separation of the waste steam is realized, the treatment capacity of the waste steam is reduced, and the obvious effects of environmental friendliness and energy conservation are achieved; and the horizontal multisource steam waste heat recovery energy-savingdevice is used as an auxiliary adjusting device of an MVR (mechanical vapor recompression) system, so that the MVR system is stably and efficiently operated, the maximum utilization of the waste steamis realized, and the energy-saving effect is obvious. The horizontal multisource steam waste heat recovery energy-saving device has the advantages of high integration level, the simple structure andlow equipment investment and can be widely applied to waste heat recovery and utilization in the industry and field of food, feed, chemical engineering, pharmacy, sewage treatment and the like.