PURPOSE: The titled microspheres of a high strength, a high modulus and a high water content, obtained by freezing an aqueous PVA solution in the form of water drops dispersed in a specified dispersing medium and crystallizing the polymer at a low temperature.

CONSTITUTION: An aqueous PVA solution kept in the form of water drops is obtained by pouring an aqueous solution containing 5W40wt% PVA of a degree of saponification ≥95mol% and an average degree of polymerization ≥1,000 into a dispersing medium such as a water-immiscible organic solvent (e.g., benzene) or an oil (e.g., silicone oil) with agitation at a speed of 200rpm. This aqueous PVA solution is frozen by cooling to -5°C or below for at least 5hr, and the polymer phase of PVA is isolated to obtain a frozen-phase molecular structure. This structure is left standing at 0W10°C for at least 10hr to crystallize the polymer phase. In this way, high-strength, high-water content, porous PVA gel microspheres of a diameter of 0.1μmW1mm, a pore diameter of 0.01W50μm, a water content of 40W95wt% and a compressive strength ≥10kg/cm2 are obtained.