A water-in-oil (W/O) emulsion ink which is suitable for use in inkjet printing and is superior in ejection performance and storage stability and low in viscosity is provided. A water-in-oil (W/O) emulsion ink which comprises a polyglycerin with a polymerization degree of not less than 3 in a water phase is provided. As an emulsifier, a polyglycerin fatty acid ester with an HLB value of 7-14 in which fatty acid moiety is oleic acid or isostearic acid, or a polyoxyethylene sorbit fatty acid ester is preferably used. The concentration of the polyglycerin in the water phase is preferably 10-70 mass % relative to 100 mass % of the whole water phase. The polymerization degree of the polyglycerin is preferably not less than 4.