A Cu2O spherical assembly particle composition is composed of Cu2O spherical assembly particles, each of which is formed by agglomerating a plurality of Cu2O ultrafine particles that have an average diameter in the range from 1 to 100 nm and a standard deviation on the diameter in the range from 0 to 10%. The Cu2O spherical assembly particles have an average diameter in the range from 0.1 to 10 μm and a standard deviation on the diameter in the range from 0 to 40%. This Cu2O spherical assembly particle composition is composed of Cu2O assembly particles with excellent uniformity, so it shows excellent properties such as realizing a good electric conductivity during a curing process for wiring. Accordingly, the spherical Cu2O assembly particle composition may be usefully used as precursors for solar energy conversion, magnetic storage medium, catalyst, gas sensor, and copper wire formation.