A robot waist skeleton, comprising: a waist inner skeleton; and a waist outer skeleton, wherein the waist outer skeleton comprises a waist outer skeleton lower part, a waist outer skeleton middle part, and a waist outer skeleton upper part; the waist outer skeleton lower part, the waist outer skeleton middle part, and the waist outer skeleton upper part being connected in sequence, and all surrounding the waist inner skeleton; characterized in that the waist outer skeleton lower part comprises a waist outer skeleton left lower part and a waist outer skeleton right lower part; wherein the waist outer skeleton left lower part and the waist outer skeleton right lower part are respectively fixed to two sides at a lower part of the waist inner skeleton; the waist outer skeleton middle part comprises a waist outer skeleton middle front part and a waist outer skeleton middle rear part; wherein the waist outer skeleton middle front part is connected to the waist outer skeleton left lower part and the waist outer skeleton right lower part respectively, the waist outer skeleton middle rear part is connected to the waist outer skeleton left lower part and the waist outer skeleton right lower part respectively, the waist outer skeleton middle front part is connected to the waist outer skeleton middle rear part, and the waist outer skeleton middle front part and the waist outer skeleton middle rear part surround a middle part of the waist inner skeleton; the waist outer skeleton left lower part is provided with a first positioning pin, and the waist outer skeleton right lower part is provided with a second positioning pin; and the waist outer skeleton middle front part is provided with a first positioning hole and a second positioning hole, the first positioning pin being inserted into the first positioning hole, and the second positioning pin being inserted into the second positioning hole. a waist inner skeleton; and a waist outer skeleton, wherein the waist outer skeleton comprises a waist outer skeleton lower part, a waist outer skeleton middle part, and a waist outer skeleton upper part; the waist outer skeleton lower part, the waist outer skeleton middle part, and the waist outer skeleton upper part being connected in sequence, and all surrounding the waist inner skeleton; characterized in that the waist outer skeleton lower part comprises a waist outer skeleton left lower part and a waist outer skeleton right lower part; wherein the waist outer skeleton left lower part and the waist outer skeleton right lower part are respectively fixed to two sides at a lower part of the waist inner skeleton; the waist outer skeleton middle part comprises a waist outer skeleton middle front part and a waist outer skeleton middle rear part; wherein the waist outer skeleton middle front part is connected to the waist outer skeleton left lower part and the waist outer skeleton right lower part respectively, the waist outer skeleton middle rear part is connected to the waist outer skeleton left lower part and the waist outer skeleton right lower part respectively, the waist outer skeleton middle front part is connected to the waist outer skeleton middle rear part, and the waist outer skeleton middle front part and the waist outer skeleton middle rear part surround a middle part of the waist inner skeleton; the waist outer skeleton left lower part is provided with a first positioning pin, and the waist outer skeleton right lower part is provided with a second positioning pin; and the waist outer skeleton middle front part is provided with a first positioning hole and a second positioning hole, the first positioning pin being inserted into the first positioning hole, and the second positioning pin being inserted into the second positioning hole.