The invention discloses a heat preservation device for high-speed railway bridge winter construction. The device comprises a box girder, water guiding pipes, a water return pipe, a switching valve, ahot water storage box, a heat preservation greenhouse and a storage battery. The water guiding pipes are arranged at the inner and outer surfaces of the box girder. The hot water storage box and the water guiding pipes form hot water circulation heat supply through a water outlet pipe and the water return pipe, and the switching valve capable of monitoring water temperature changes is arranged atthe joint of the water return pipe and the water guiding pipes; the hot water storage box is connected with a solar heating device through a circulating water pipe, and an electric heating component is arranged in the hot water storage box to be connected with the storage battery. When sunlight is not enough due to the poor weather condition, the storage battery is used for performing auxiliary heating on water in the water storage box. The device converts light energy into heat energy, the box girder of the bridge structure is uniformly heated, the heating and heat preservation quality are effectively ensured, and the device has the advantages of being clean, environmentally friendly, free of contamination, and uniform in heat supply.