A dissolvable nano web porous film has a network structure and a large specific surface area. The network structure is formed by stacking nano fibers that have a thickness of 10&tilde50,000 nm. The nano fibers are formed of a composition comprising nano fiber forming polymer, a gelling agent, a plasticizer, an optional active component and an optional additive. A method of preparing a dissolvable nano web film comprises producing a polymer melt or solution formed of a composition that comprises a nano fiber forming polymer, a gelling agent, a plasticizer, an optional active component and additives, spinning the melt or solution to form a nano web porous film having nano webs stacked in a network structure, drying the nano web porous film, and stabilizing the nano web porous film. The porous film has a 5&tilde5000 times higher specific surface area and a 2&tilde20 times faster dissolving time than a conventional film. The dissolvable nano web porous film has excellent dissolvability and solubility.
