Abstract: The invention is an endotracheal intubation for preventing injury to throat, vocal cords and trachea. The endotracheal intubation comprises a hollow intubation body with a variable outer diameter. The hollow intubation body comprises a front end and a tail end, an inner intubation wall and an outer intubation wall, and having a retracted state with a smaller outer diameter and an expanded state with a larger outer diameter. When the endotracheal intubation inserted into a patient’s trachea needs to be replaced, as long as the hollow intubation body of the new endotracheal intubation is in the retracted state, it can be inserted into the hollow intubation body to be replaced, and when reaching the position, the hollow intubation body to be replaced is withdrawn, and finally the new hollow intubation body is changed into the expanded state, i.e. the replacement operation of the endotracheal intubation is completed.