In solid tumors, cancer cells are exposed to microenvironment stress, including hypoxia and insufficient nutrients. An acidic microenvironment in tumors is facilitated by the increase in synthesis of lactic acid; this is known as Warburg effect. We previously showed that B16F10 melanoma cells were induced autophagic cell death by glucose-deprivation stress, and lactic acid suppressed the cell death through the inhibition of autophagy. In this study, effects of lactic acid on cell death of B16F10 cells under hypoxic and glucose-depleted double stress conditions were investigated. The double stress promoted autophagic cell death earlier than glucose-depleted stress alone. Lactic acid repressed the double stress-induced cell death by inhibiting autophagy. These results suggest that lactic acid serves for cell survival under microenvironmental stress conditions in B16F10 melanoma cells.