A water-base ballpoint ink prepared, without using conventional water-soluble organic solvents which have been used for ink in the prior art, e.g., glycols, glycerin or glycol ethers, by adding at least one member selected from among reducing sugars mainly comprising maltitol, reducing sugars mainly comprising sorbitol, reducing dextrin, reducing maltodextrin, DOLLAR g(a)-cyclo-dextrin, DOLLAR g(b)-cyclodextrin and maltosylcyclodextrin as the componen t for protecting a ballpoint tip from drying, at least one member selected from among adducts of polyglycerol with alkylene oxides, adducts of glycerol with alkylene oxides and adducts of trimethylolpropane with alkylene oxides as the component for protecting drawn lines from feathering, improving the smoothness of ink flow, and retaining the lubricity thereof, and a viscosity modifier. The ballpoint ink gives good feelings in writing and is excellent in the smoothness of ink flow and the protection of a ballpoint tip from drying.