Based on the actual composition and physical properties of diesel fuel, n-dodecane was selected as the test fluid to observe and analyze the dynamic behavior characteristics of a single 100 ℃ droplet impacting cryogenic walls. The research results showed that, unlike the low-temperature wall impingement process of room temperature droplets, the upper surface of the liquid film in the process of high-temperature droplet impingement produced a translucent shadow structure which spreaded with the liquid film. As the wall temperature decreased and the initial velocity increased, the color of the shadow structure deepened, and the structure was gradually twisted in a wave-like shape. The spreading process of high-temperature droplet impacting the wall was also greatly changed compared with that of room temperature droplets. The existing models for predicting the maximum spreading factor β_max and the time of predicting the maximum spreading diameter t_max under room temperature conditions are not applicable to the test conditions of 100 ℃ droplet impacting the low-temperature wall. An analytical fit was obtained to model the liquid film spreading of high temperature droplet hitting the wall. The wall splashing threshold of 100 ℃ high-temperature droplets also changed greatly compared with that of room temperature droplets, and a droplet splashing threshold model suitable for this experiment by comparing and analyzing the existing models was obtained.