A mathematical model was developed to describe kinetics of the low-pressure methanol synthesis from syngas over Polish commercial Cu/ZnO/MnO3/Al2O3 (BT-1) catalyst. A rigorous reaction network including methanol formation from CO and CO2 and the water gas-shift reaction was a basis for the derivation of the rate expressions. The kinetic parameters were estimated by nonlinear regression of the experimental data obtained in a stirred tank slurry reactor. Model simulation showed that under reaction conditions, methanol is formed mainly from CO2.