Waterborne strippable coating for temporarily protecting metal

The invention discloses a waterborne strippable coating for temporarily protecting metal. The waterborne strippable coating is prepared in the following steps of: firstly, sequentially adding a wetting agent, a dispersing agent and a thickening agent into water, and stirring the mixture; then, dispersing the mixture at high speed of 1200-2500rpm to obtain a stable dispersion liquid; then, adding waterborne polyurethane and a styrene-acrylic emulsion in the dispersion liquid while stirring, and stirring; and adjusting the stirring speed to 200-600rpm, and adding a flatting agent, a coalescing agent, a waterborne scaling agent, a waterborne corrosion inhibitor and a defoaming agent. Tests prove that the coating has the average tensile strength of 10.78MPa and the average elongation at break of 353.5% when the dry film thickness of the waterborne strippable coating is 0.08-0.09mm. After a test for the water resistance and 3% NaCl solution resistance of the coating is carried out over 48 hours, no remarkable bubbling and rusting phenomena are caused; the coating has better corrosion resistance and an uvioresistant function.