An alkyl-modified PVA solution is provided which has low viscosity at high temperatures leading to superior handleability, accompanied by rapidly increased viscosity upon lowering of the temperature, even in the case in which the concentration of the alkyl-modified PVA in a solution is increased. An alkyl-modified vinyl alcohol polymer solution containing an alkyl-modified vinyl alcohol polymer, a surfactant and water. The alkyl-modified vinyl alcohol polymer has a monomer unit that includes an alkyl group having 5 to 29 carbon atoms. The percentage content of the monomer unit is no less than 0.05 mol % and no greater than 5 mol %. The degree of saponification of the alkyl-modified vinyl alcohol polymer is no less than 20 mol % and no greater than 99.99 mol %. The surfactant is a compound represented by the following formula (I) having hydrophilic groups X1 and X2, and an alkyleneoxy group having 3 to 5 carbon atoms (—R1—O—). X1—OR1—OmR2—X2  (I)