This study evaluated the effects of heat treatment on gastrodin and gastrodigenin content, and antioxidant activities, in Gastrodia elata Blume. Gastrodin and gastrodigenin content was analyzed post-method validation, and antioxidant activity evaluation, including assessing total polyphenol content, DPPH, and ABTS radical scavenging activities, was done. The validation of the analysis method demonstrated excellent linearity. The limits of quantification of gastrodin and gastrodigenin were 2.89 and 3.47 μg/mL, respectively. Moreover, the results of intra- and inter-day precision analysis demonstrated relative standard deviation values, within 5%. The recovery rates for gastrodin and gastrodigenin were 97.22~98.85 and 97.99~99.91%, respectively, indicating good accuracy. Under different heat treatment conditions, gastrodin and gastrodigenin content significantly increased (p<0.05), ranging from 91.15 to 310.27 and 559.66 to 830.02 mg/100 g DW, respectively. Additionally, the total polyphenol content exhibited a significant (p<0.05) increasing trend, ranging from 1,444 to 1,798 mg/100 g DW, as the temperature and time of heat treatment increased. The DPPH and ABTS radical scavenging abilities demonstrated an increasing trend at 120℃ during heat treatment. These research findings are expected to enhance our understanding of the changes in gastrodin and gastrodigenin content, and antioxidant effects in Gastrodia elata Blume during heat treatment.