Vacuolar-type H⁺-ATPase (V-ATPase) is a kind of hydrogen ion transport enzyme, in which subunit c plays an important role in maintaining the normal acid-base environment in cells. To investigate the function of the V-ATPase subunit c in under high pH stress, the full-length cDNA of V-ATPase subunit c in , was first cloned by rapid amplification of cDNA ends (RACE). Then, the response of under high pH stress was detected. Subsequently, RNA interference (RNAi) technology was used to verify gene function. The full length of cDNA sequences consisted of 2128 base pairs (bp), including a 483 bp open reading frame (ORF), which encodes a 160-amino acid peptide with four transmembrane domains. The predicted protein molecular weight of the protein was 16 kD, and the theoretical isoelectric point (pI) was 7.82. Homology and phylogenetic analysis showed that the deduced amino acid sequence was highly conservative, had the highest amino acid sequence identity (99%) with as well. Results of RT-qPCR showed that , and the expression level in the gills was significantly higher than that in other tissues (FcVHA-c reached a peak at 12 h, which was 1.206 times that of the control group, and reached the lowest value at 48 h, which was 0.166 times that of the control group. Under pH 9.2 stress, the expression level of peaked at 1 h. It was 1.577 times that of the control group and reached its lowest value at 12 h, which was 0.104 times that of the control group. The results showed that high pH had a certain inhibitory effect on by RNAi, under the high pH stress, resulted in mortality that was significantly higher than that in the control group ( may play an important role in ion regulation under the condition of high pH stress, whereas excessive high pH-stress inhibits the ability to regulate .