<p>A grinding work liquid for aluminum or its alloy that in the grinding work of a substrate of aluminum or its alloy, is capable of satisfactorily inhibiting any overall or local clogging on a substrate contact surface of whetstone and also satisfactorily inhibiting any scratching (blemishing) of a substrate surface to be ground attributed to grinding sludge and dropped abrasive grains. The grinding work liquid for aluminum or its alloy is characterized by containing (A) 2 to 15 wt.% C12-C18 monocarboxylic acid, (B) 3 to 15 wt.% alicyclic dicarboxylic acid, (C) water-soluble amine in at least an equivalent weight for neutralization of the monocarboxylic acid (A) and alicyclic dicarboxylic acid (B), and (D) 15 wt.% or more nonionic surfactant.</p>
