Abstract: In this study, Gastrodia elata was treated with compound enzyme, and Lactiplantibacillus plantarum STDA6 was used as fermentation agent to prepare fermented G. elata oral liquid. Orthogonal experiment was used to optimize the preparation process of lactic acid bacteria fermented G. elata oral liquid. The results showed that the optimal process conditions for enzymatic hydrolysis of G. elata were carried out after mixing pectinase, cellulase, tannins and α-amylase, and the optimal process conditions for enzymatic hydrolysis of complex enzymatic hydrolysis were: the ratio of material to liquid (g:mL) was 1:11, the amount of enzyme was 0.4%, the pH value was 4.0, the enzymatic hydrolysis temperature was 50 ℃, the enzymatic hydrolysis time was 180 min. The optimum technological conditions of lactic acid bacteria fermenting G. elata oral liquid were as follows: inoculation amount with 1×10⁵ CFU/mL, fermentation time for 12 h, fermentation temperature at 37 ℃, sucrose addition with 10%. The average number of L. plantarum STDA6 in G. elata oral liquid fermented by lactic acid bacteria was 2×10⁸ CFU/mL, pH value was 3.5, the total number of bacteria was less than 10 CFU/mL and coliform, mold, yeast, Staphylococcus aureus, Salmonella were not been detected, which complied with the relevant requirements of GB/T 31326-2014 ‘Botanical Beverage’.