Updated project metadata. Here, we define the proteomic response of the early divergent liverwort Marchantia polymorpha during infection with the oomycete pathogen Phytophthora palmivora. We sampled whole liverwort thalli that were mock-inoculated (water) or infected with P. palmivora zoospores at 4 and 8 days post inoculation (dpi). This analysis revealed the protein profiles of liverworts during the biotrophic (4 dpi) and necrotrophic (8 dpi) stages of pathogen infection. In combination with additional omics datasets, our analyses reveal conserved aspects in the molecular response to pathogen infection in liverworts and angiosperms.