Viscoelastic behavior of the blend system of gelatin and κ-carrageenan wa examined. From pH dependence of the viscosity and the experiments using phthalated gelatin, we have concluded that the increased viscosity of the blend solutions is caused by formation of a gelatin-carrageena complex through electrostatic interaction. The blend of gelatin and the jet-treated carrageenan exhibited little pH dependence of the viscosity. The jelling characteristic of the blend solutions was examined. Addition of the jet-treated carrageenan to gelatin showed no change in the setting point but the clearly increased elasticity of the gel.