The aim of this study was to investigate the effects of lactic acid bacteria fermentation on the nutritional and flavor profiles of Gastrodia elata. Five lactic acid bacteria strains were selected; comparative analysis was conducted. Analysis of nutritional and bioactive compounds before and after fermentation revealed that in the fermented G. elata groups, total sugar content decreased significantly by 26.77%~32.17% (P<0.05), whereas lactic acid content increased significantly by 45.41%~74.96% (P<0.05), with the LPL strain exhibiting the strongest glycolytic activity. Gastrodin content decreased significantly (P<0.05), whereas p-hydroxybenzyl alcohol levels increased. Total phenolic content increased by 31.69%~59.22% (P<0.05), with the LC strain exhibiting optimal performance in efficient gastrodin biotransformation and enhancement of total phenolic compounds. Additionally, antioxidant capacity was significantly improved after fermentation, as evidenced by increased ABTS and DPPH radical scavenging rates (17.86%~35.72% and 62.61%~98.42%, respectively; P<0.05). Flavor profile analysis revealed that fermentation enriched the volatile compound composition of G. elata. The BAN group developed the most distinctive and complex flavor profile, whereas the LRH group maintained the closest flavor resemblance to the unfermented CK group. Electronic tongue analysis revealed no significant changes in bitterness, astringent aftertaste, or bitter aftertaste. However, notable enhancements were observed in sourness, saltiness, and umami richness, along with a significant reduction in astringency (P<0.05). In conclusion, lactic acid bacteria fermentation improves the overall quality of G. elata in terms of nutrition, flavor, and functional activity. This finding provides a reference for developing G. elata-based food products.