A composition for copper patterning and a method of copper patterning using the composition are provided, which composition is excellently safe in copper patterning, sintering at lower temperatures, and capable of forming a highly conducive copper pattern of a desired shape even on a plastic substrate. The composition contains Component A: a copper β-ketocarboxylate compound of formula (1): (R1, R2: H or C1-C6 straight- or C3-C6 branched-hydrocarbon group, etc.); and based on 1 mol of this compound, Component B: an amine compound having a boiling point of not higher than 250° C. at 0.1 to 500 mol; and Component C-1: an organic acid having pKa of not more than 4 at 0.01 to 20 mol, and/or Component C-2: an organic copper compound composed of copper and an organic acid having pKa of not more than 4 at 0.01 to 100 mol. The composition is useful in the field of electronics.