Preparation method for polyvinyl alcohol sponge microneedle

The invention relates to a preparation method for a polyvinyl alcohol sponge microneedle. The method includes the steps that a polyvinyl alcohol solution is prepared, a foaming agent is added into the polyvinyl alcohol solution and evenly stirred, then a formaldehyde solution and a concentrated sulfuric acid solution are sequentially added, and a mixed solution is prepared after even stirring; and the mixed solution is injected into a microneedle mold and solidified, and the polyvinyl alcohol sponge microneedle is obtained after demolding and cleaning. Formaldehyde is used as a cross-linking agent, the obtained polyvinyl alcohol sponge microneedle is high in strength and can be easily pierced into skin, washed with clean water repeatedly and used for continuous and repeated dosing, and the safety and practicability of the polyvinyl alcohol sponge microneedle are greatly improved.