A method of producing an entangled sheet of microfine long fibers using long fibers for forming microfine fibers. The method includes a step of forming a long-fiber web made of long fibers for forming microfine fibers, at least one component of the long fibers being a water-soluble, thermoplastic polyvinyl alcohol resin; a step of entangling the long-fiber web to form a long-fiber entangled sheet; a step of shrinking the long-fiber entangled sheet to form a long-fiber shrunk sheet; and a step of converting the long fibers for forming microfine fibers in the long-fiber shrunk sheet to microfine long fibers, thereby producing the entangled sheet of microfine long fibers. The step of entangling is conducted so as to allow the long-fiber entangled sheet to have an interlaminar peel strength of 2 kg/2.5 cm or more. The step of shrinking is conducted so as to shrink in an areal shrinkage of 35% or more.