A liquid atomizing device includes a medical solution cup connected to an air pump, and an output cover installed onto the medical solution cup and including an atomizing socket formed in the outer cover, and the top of the atomizing socket cover has a linear opening and a drainage groove for increasing the flow of a medical solution. When the medical solution is guided to flow upwardly through the drainage and sprayed from a specially designed linear opening to the outside through the drainage groove due to a high speed airflow, the medical solution is collided with a barrier rod disposed above the linear opening to form an atomized medical solution, and the linear opening has the effect of atomizing the medical solution stably.