OBJECTIVE： To investigate the stability of hypoglycemic candidate 6-benzyloxy-9-（-4-chlorobenzoyl）- tetrahydrocarbazole-3-carboxylic acid （abbreviated “Zg02”） in artificial gastrointestinal fluid， and to analyze its catabolites. METHODS： Using indometacin as internal standard， HPLC method was used to detect the contents of Zg02 incubated in blank artificial gastric fluid （pH 1.3，no enzyme）， blank artificial intestinal fluid （pH 6.8， no enzyme）， artificial gastric fluid （pH 1.3， containing pepsin） and artificial intestinal fluid （pH 6.8， containing trypsin） for 6 h. The remaining percentage was calculated. UPLC-Q-TOF was used to analyze TIC of control sample （Zg02 control solution）， blank sample （incubation solution without Zg02） and incubated sample （incubation system with the most obvious change of Zg02 concentration in stability test）； difference peaks were compared， and catabolites were inferred by MS map. RESULTS： The remaining percentage of Zg02 incubated in blank artificial intestinal fluid and artificial intestinal fluid for different time ranged 90％-110％. Zg02 was unstable in acidic condition （pH 1.3）. The remaining percentage was about 50％ after incubated for 3 h. There was no significant change in the remaining percentage of continuous incubation. The remaining percentage of artificial gastric fluid （including enzymes） was lower than that of blank artificial gastric fluid （without enzymes）， but the difference was not obvious. The difference of incubated samples， control samples and blank samples was reflected that the retention time was 5.23 min under negative mode scanning， MS of chromatographic peaks at this time point showed that quasi-molecular ion peaks of m/z 320.127 2 [M-H]－ existed in low energy scanning channels and fragment ion peaks of 230.081 5 and 276.138 2 could be seen in high energy channels. It was speculated that amide bond breakage may occur in Zg02 under acidic （pH 1.3） conditions to generate 6-benzyloxy-tetrahydrocarbazole-3-carboxylic acid. CONCLUSIONS： Zg02 is stable in artificial intestinal fluid； Zg02 is not stable in acidic condition （pH 1.3）， and is basically not affected by pepsin， the degradation products may be 6-（benzyloxy）-tetrahydrocarbazole-3-carboxylic acid.