To examine the effects of sodium pyruvate (SP) on metabolic acidosis. For the in vivo experiments, we evaluated effects of SP on an ammonium chloride (NH4Cl)-induced hyperchloremic acidosis rat model. SP was infused at overall doses of 2, 4, and 6 mmol·kg(- 1) for the SP1, SP2, and SP3 groups, respectively. Treatment with sodium bicarbonate (SB) was used as a positive control (2 mmol·kg(- 1)), and treatment with normal saline (NS) was used as a volume control (2 mL·kg(- 1)). Blood was sampled from the ophthalmic venous plexus for pH, blood gases, electrolytes, glucose, creatinine (Cr), and urea analysis after injection. For the in vitro experiment, propionate was applied to induce intracellular acidosis in human endothelial cells. Intracellular pH (pHi) was fluorimetrically measured after the addition of SP. In the in vivo study, the pH of SP1 group showed no significant difference compared with that of the NS group. The SP2 and SP3 groups had a higher pH than the NS group (P < 0.01). The SP3 group had a higher pH than the SB group (P < 0.05) and SP1 group (P < 0.05). Moreover, SP treatment ameliorated the abnormality of calcium and decreased the blood potassium levels. The SP3 group had higher glucose levels than SP1 group (P < 0.05). No significant differences were observed between all the groups in the plasma Cr and urea levels. In the in vitro study, the pHi increased immediately after the addition of SP. The data suggest that intravascular treatment with SP represents a novel therapeutic strategy to ameliorate metabolic acidosis.