To provide an excellent heat insulating paper container which makes heat of heated contents such as a beverage and fast food hard to conduct, even if a barrel part of a paper cup is held by hand for a long time after the heated contents are put into the paper cup.

Characteristically, this heat insulating paper container is composed of a paper cup body, in which an outward curl part is provided at an upper opening edge, and an outer cylinder made of paper, which is opened in both upper and lower positions and in which an inward curl part is provided at a lower opening edge; the outer cylinder is large enough for an inner surface of an upper opening thereof to be brought into contact with an outer peripheral surface of a side wall immediately below the outward curl part of the paper cup body, and for the inward curl part of the lower opening edge thereof to be brought into contact with the outer peripheral surface of the side wall of a lower part of the paper cup body; the outer cylinder covers the paper cup body, the inner surface of the upper opening of the outer cylinder is bonded to the outer peripheral surface of the side wall near an area above the barrel part of the paper cup body, and the outer cylinder and the paper cup body are integrated with each other, so that the heat insulating paper container can be formed; and a part or the whole surface of the outer periphery of the barrel part of the heat insulating paper cup, in which a void is formed between the paper cup body and the outer cylinder, is covered with a protective cover which is composed of a heat insulating raw material.