Spray drying is the most commonly used method of preparing probiotic microcapsulation. Because of the difficulty in the study of the drying process of the droplets in the spray drying tower， the experiment is carried out to study the protective effects of the different DE syrups and different melting palm oil on the survival rate of L. plantarum in the simulated spray drying conditions using the single droplet drying technology. The results showed that the survival rate of high melting point palm oil droplets was higher than that of low melting point palm oil during the drying process under different drying conditions. It was observed that there was no free L. plantarum on the surface of the single droplet after drying by Scanning electron microscopy（SEM）， and the higher the DE value of the syrup was more favorable for the stability of the surface structure combined with the changes in droplet of moisture content. The survival rate of L. plantarum was mainly related to the temperature of the droplets by analyzing the droplet drying parameters and the thermal stability of the emulsion. The higher the melting point of the palm oil， the more heat is absorbed during the drying process so that L. plantarum can get a higher survival rate.