To obtain the subject composition having a low melt viscosity, good in heat resistance and cohesive strengths and presenting no bleed by mixing a copolymer having a low molecular weight to a block polymer as a melt viscosity reducing agent.

This hot melt resin composition is obtained by mixing (A) a block copolymer as a main material with (B) a block copolymer having a lower molecular weight than that of the component (A) as a melt viscosity reducer. The wt. average molecular weight of the component B is <1/2 of the wt. average molecular weight (preferably 5,000-500,000) of the component A. The component A and the component B are both preferably (meth)acrylic block copolymer. The 180°C viscosity of the composition is preferably ≤7/10 of the 180°C viscosity of the component A. The component A and the component B are each obtained by ionic polymerization using an organic metal compound as an initiator. The weight ratio of the component A over the component B, (the component A)/(the component B), is preferably 1/5-2/1.