It is proposed to establish a synthetic route of pyruvate obtained from malic acid by whole cell biotransformation using Escherichia coli. With Escherichia coli BL21 (DE3) as the host， endogenous malice enzyme (ME) and aldose reductase (AR) from Candida boidinii were co-overexpressed on pET28a， and catalytic key factors such as cell concentration， substrate concentration， temperature and pH were investigated. Activities of malic enzyme from Escherichia coli and aldose reductase from Candida boidinii were (2.8±0.21)， (3.1±0.34) U/mL respectively. The suitable catalytic conditions were as follows， the cell concentration of bacterial OD600nm value was 30， the mass concentration of substrate malic acid was 30 g/L， the molar ratio of xylose to malic acid was 1.0， temperature was 40 °C， the pH value of the reaction system was 7.8， pyruvate yield was up to 23.16 g/L. This study provides a new method for the biological production of pyruvate.