The invention discloses a novel one-piece knitted pantyhose. The pantyhose comprises stockings, knee connecting areas are in sewing connection with the stockings, and thigh knitted sleeves are sewed on the outer walls of the tops of the knee connecting areas; a T-shaped area is sewed on the inner walls of the opposite sides of the thigh knitted sleeves, a zipper is arranged on the edge of the outer wall of the top end of the T-shaped area, the zipper comprises two zipper sides with the same specification, and the two zipper sides are meshed with each other; one zipper side is sewed on the edgeof the outer wall of the top end of the T-shaped area, a belly heat preservation sleeve is fixed to the outer wall of the top of the T-shaped area through a zipper, and an elastic structure is arranged at the joint between the T-shaped area and the zipper and comprises a pulling passage and a pulling elastic cord; the pulling elastic cord is slidably connected to the inner wall of the pulling passage. According to the novel one-piece knitted pantyhose, through the detachable belly heat preservation sleeve, a warm paste can be loaded in a hidden bag for warming the belly of a woman in the menstrual period, an electric magnet therapy area can be utilized for electric magnet therapy, and an auxiliary effect is achieved on the physical health of the woman.