A thin paper, which has a basis weight of 5 to 15 g/m.sup.2 and a thickness of 10 to 50 .mu.m and which comprises at least 10% by weight, based on paper-constituting fibers, of a drawn polyester fiber having a single filament fineness of 2.5 denier or less, a filament length of 15 mm or less and a birefringence (.DELTA.n) of at least 0.03. This thin paper comprises at least one member selected from the group consisting of urethane resins and epoxy resins at crossing points and surfaces of the filaments in an amount of 3 g/m.sup.2 or less of the thin paper. This thin paper is a valuable as a heat-sensitive stencil printing paper.