NOVELTY - A silver compound is mixed with amine containing an aliphatic hydrocarbon monoamine (A) containing 6C or more aliphatic hydrocarbon group, aliphatic hydrocarbon monoamine(s) (B) containing 5C or less aliphatic hydrocarbon group, and aliphatic hydrocarbon diamine (C) containing 8C or less aliphatic hydrocarbon group, to produce complex compound. Obtained complex is heated and decomposed to form silver nanoparticles. Silver nanoparticles are dispersed in dispersive solvent containing aliphatic hydrocarbon to obtain silver nanoparticle-containing ink.    USE - Manufacture of silver nanoparticle-containing ink (claimed) used for forming electroconductive film and electroconductive wiring. Uses include but are not limited to electromagnetic wave control material, circuit board, antenna, heat sink, liquid crystal display, organic electroluminescent display, field emission display, solar cell, light emitting device element, organic transistor, capacitor, electronic paper, flexible battery, flexible sensor, membrane switch and touch screen.    ADVANTAGE - The method efficiently provides silver nanoparticle-containing ink having low heat resistance and excellent electroconductivity and productivity in short period of time, by low-temperature baking.    DETAILED DESCRIPTION - A silver compound is mixed with an amine containing an aliphatic hydrocarbon monoamine (A) composed of 6C or more aliphatic hydrocarbon group, and a amino group, aliphatic hydrocarbon monoamine(s) (B) composed of 5C or less aliphatic hydrocarbon group and a amino group, and aliphatic hydrocarbon diamine (C) composed of 8C or less aliphatic hydrocarbon group and two amino groups, to produce a complex compound containing silver compound and amine. The obtained complex is heated and decomposed to form silver nanoparticles. The obtained silver nanoparticles are dispersed in a dispersive solvent containing aliphatic hydrocarbon to obtain silver nanoparticle-containing ink. An INDEPENDENT CLAIM is included for silver nanoparticles-containing ink.