The gelation behaviors of high molecular weight poly(vinyl alcohol)(PVA) solutions were investigated by the measurements of the rate of phase separation and the rate of gelation. PVA solutions were prepared with dimethyl sulfoxide(DMSO)/water mixed solvents in various compositions. Gelation time was gradually shortened with increasing DMSO content in the mixed solvent up to 60%(vol.). Also, the gelation was faster for higher molecular weight PVA due to easier network formation with higher degree of polymerization. Gels of PVA solutions formed at $0^{circ}C$ showed high transparency with the exception of DMSO/water(v/v)=0/100, 90/10, 100/0 solutions. Particularly, the gel formed in the mixed solvent of DMSO/water(v/v)=80/20 still maintained its transparency after 20,000 min. This means that the most stable PVA gel can be made with the mixed solvent of DMSO/water(v/v)=80/20.