Streptococcus pneumoniae is the most common pathogenic bacterium of pneumonia and can cause death. Here, we examined the impact of Baicalein on mouse mortality caused by Streptococcus pneumoniae infection. Baicalein protected mice from Streptococcus pneumoniae-induced deaths. Baicalein reduced alveolocapillary membrane permeability, lung infiltration of inflammatory cells, inflammatory cytokine production and pulmonary cell apoptosis. These evidences show that Baicalein is useful in the therapy of a severe form of pneumonia that can cause deaths.