To provide a heat-insulating paper cup having a good appearance because wrinkles are invisible from the outside of the cup, and consisting of a paper cup main body and a cylindrical member made of paper.

The lower part of a cylindrical member (20) made of paper is formed in such a manner that in the case where the cylindrical member is fitted onto a paper cup main body (10), the annular leg part (14) of the paper cup main body is concealed by the folded part (21) of the cylindrical member, which is folded in the form of an inverted N shape in section. When the cylindrical member is fitted onto the barrel part (11) of the paper cup main body, the forward end portion (22) of the cylindrical member, where the folded part (21) is formed, is fixed to the outer face of the annular leg part (14) provided at the lower edge of the barrel part of the paper cup main body, and the upper end (23) of the cylindrical member is contacted with and fixed to the lower edge of the mouth edge portion of the barrel part. A heat-insulating space layer (30) is provided between the barrel part of the paper cup main body and the cylindrical member made of paper.