Abstract: Provided is a medical material comprising a molded hydrogel obtained by pouring an aqueous solution containing not less than 6 wt. % of a polyvinyl alcohol which has a degree of hydrolysis not less than 97 mole % and average polymerization degree not less than 1,100, into a desired shape of a vessel or mold, freeze-molding the aqueous solution at a temperature lower than -5.degree. C., then partially dehydrating the resulting molded product without thawing it up to a percentage dehydration not less 5 wt. %, and if required, immersing the partially dehydrated, molded product in water to attain a water content thereof in the range of 45 to 95 wt. %.