The invention relates to a konjac glucomannan air purifying nano screen window and a preparation method thereof. The preparation method of the konjac glucomannan air purifying nano screen window comprises the following steps of preparing a film stock solution, preparing a non-woven fabric, making a spinning solution, and preparing a nano window screen by using an electrospinning machine. The konjac glucomannan air purifying nano screen window provided by the invention adopts konjac glucomannan as a main material, and has higher tensile strength and higher antibacterial effect than a polyethylene material, and can keep the indoors clean and hygienic for a long time; nano cobalt ferrite is added to enhance the adsorption effect of the screen window to particles, enhance the weather resistance and toughness, improve the weathering resistance and prolong the service life; the non-woven fabric and a filter membrane layer are both made of natural ingredients, so that the screen window can becompletely biodegraded after being discarded, and is environmentally friendly and low carbon. The konjac glucomannan air purifying nano screen window provided by the invention has the advantages of small and uniform pore size, large tensile strength, good toughness, good gas permeability, anti-aging, convenience in material obtaining, low price and long service life.