The invention relates to a series humanoid robot, belonging to the robot field. The invention adopts a digital servo motor as a joint driving device; carbon fiber material is used to design a carbon fiber double-pipe structure and is used on structural parts such as backbone, big arm, small arm, thigh and calf; a similar joint frame type of structure is adopted to design a trunk so as to improve the structural intensity and stability; a pull spring mechanism is used to design a head buffer device so as to enhance the impact resistance of the head; finally a nineteen free DEG C series humanoid robot is realized, which is big in dimension, light in mass, strong in motion flexibility and has a head buffer mechanism. The invention solves the problems of the previous humanoid robot, the motor of which has too much load, is hard to control and is easily burn due to the overweight of the self structure, and provides an effective solution to the protection of the head when the robot falls down or is collided.