This application provides a negative electrode plate, a lithium metal battery, and an apparatus including the lithium metal battery. The negative electrode plate includes a negative electrode current collector and a lithium-metal negative electrode disposed on at least one surface of the negative electrode current collector, where a polymer protective film is disposed on a surface of the lithium-metal negative electrode away from the negative electrode current collector, the polymer protective film includes a citric acid copolymer, and a number-average molecular weight Mn of the citric acid copolymer is 10,000 to 1,000,000. In this application, a polymer protective film with high tensile strength, high puncture strength, high elongation, and high electrolyte holding capacity may be formed on the surface of the lithium-metal negative electrode in the negative electrode plate.