The invention relates to a 
polyurea-based 
grease additive composition. Components and percentage content of the 
polyurea-based 
grease additive composition are that: 
base oil is 
mineral oil and 
synthetic oil or blending oil of the 
mineral oil and the 
synthetic oil, and the content of the 
base oil is from 71% to 91.5%; a 
thickening agent is composed of a common reactant of 
isocyanate, 
fatty amine and alicyclic amine, and the content of the 
thickening agent is from 6% to 12%; an 
antioxidant uses amine antioxidants, and the total content of the 
antioxidant is from 0.5% to 3%; an extreme-pressure agent uses a mixture of sulfurized 
isobutylene, dialkyl group dithiophosphate and dialkyl group dithiocarbamic acid, and the total content of the extreme-pressure agent is from 0.5% to 5%; the content of an antirusting agent is from 0.5% to 3%; an antiwear agent is triphenyl 
thiophosphate and 
thiophosphoric acid ester or a mixture of the triphenyl 
thiophosphate and the 
thiophosphoric acid ester, and the total content of the antiwear agent is from 0.5% to 3%; and 
tackifier is polyisobutene and 
polymethyl methacrylate or a mixture of the polyisobutene and the 
polymethyl methacrylate, and the total content of the 
tackifier is from 0.5% to 3%. Due to the fact that appropriate 
raw material proportion is selected and used, 
grease has good high-temperature performance, a dropping point is higher than 260 DEG C, and the 
polyurea-based grease additive composition has a good water-resisting property, high and low 
temperature resistance and extreme pressure anti-wear performance, and can be applied to 
lubrication of each key running part of a continuous casing 
machine.