Abstract: A one-component solvent-free anti-sagging polyurethane waterproof coating, a production system and a production method thereof; the coating comprises the following components in parts by weight of: 25-50 parts of a polyurethane prepolymer, 10-20 parts of a heavy filler, 10-20 parts of a nano-filler, 0.05-0.2 parts of a composite catalyst, 0.1-0.3 parts of a physical defoamer, 0.1-0.3 parts of a chemical defoamer, 5-20 parts of a plasticizer, 0.1-0.3 parts of a dispersant, 0.05-0.2 parts of a dehydrating agent, and 2-5 parts of a reactive diluent, the polyurethane prepolymer is made by reacting 19-72 parts of a composite resin diol, 1-10 parts of a polyether triol, 0-32 parts of a composite isocyanate, and 0.1-0.5 parts of an aliphatic amine chain extender. The coating can not only be applied to a facade or a slope, has a strong anti-sagging property, maintains good physical properties, but also enables continuous production and increases work efficiency.