To investigate the changes in nutritional characteristics of Amanita caesarea under different drying treatments, in this study, we used fresh A. caesarea as raw material and subjected them to three drying methods: vacuum freeze drying, hot air drying, and natural sun drying. The 10 kinds of minerals, 18 kinds of amino acids, volatile substances, fatty acids, crude protein, total sugar, crude fat, crude fiber, ash and riboflavin in Amanita caesarea after different drying treatments were analyzed by atomic absorption spectrophotometry, high performance liquid chromatography, gas chromatography-mass spectrometry, gas chromatography, Coomassie brilliant blue method, phenol-sulfuric acid method, Soxhlet extraction method, acid-base hydrolysis method of fiber analyzer, determination method of total ash in food and fluorescence spectrophotometry. The results showed that vacuum freeze drying yielded the highest levels of crude protein, total sugar, and riboflavin, different drying methods had a significant impact on riboflavin content, while their effects on crude fat, crude fiber, and ash were relatively small. The mineral calcium (Ca) content was highest in hot air drying, whereas iron (Fe), sodium (Na), magnesium (Mg), zinc (Zn), and manganese (Mn) were highest in vacuum freeze drying. The total amino acid content, amino acid score, and essential amino acid index were ranked as follows: vacuum freeze drying>natural sun drying>hot air drying. The number of volatile compounds was highest in vacuum freeze drying, followed by natural sun drying and hot air drying. The types and contents of fatty acids were vacuum freeze drying>natural sun drying>hot air drying. Based on the above three drying methods, it could be seen that vacuum freeze drying had the best retention effect on the types and contents of nutritional in A. caesarea, followed by natural sun drying and hot air drying. Therefore, vacuum freeze drying was more suitable for drying A. caesarea. This study provides a theoretical basis for more scientific and rational drying of A. caesarea and other edible fungi by investigating the retention basic nutrients and volatile substances under three different drying treatments.