The antibacterial activity of Eu3+-doped SrSnO3-type materials against Staphylococcus aureus (Gram-pos.) and Escherichia coli (Gram-neg.) bacteria is described. Two Eu3+-doped SrSnO3 perovskites - (SrEu)SnO3 and Sr(SnEu)O3 - were synthesized by a modified-Pechini method and characterised by XRD, FT-IR, FE-SEM, HR-STEM/EDX, BET, Photoluminescence (PL), UV-Vis, Q-band EPR and XPS to understand the impact of Eu doping on the materials′ properties. Structural characterisations indicated that the desired perovskite phase completely crystallized after calcination at 700 °C. Long and short-range structural changes were observed as a function of the site-doping with Eu and calcination temperature Small sp. surface area, which varied from 8.09 to 13.28 m2/g, was observed for the samples. Nonetheless, the formation of nanoparticles under 10 nm, clusters of nanoparticles> 100 nm, and nanorods with 100-600 nm x 10-50 nm (length x width) was evidenced. Eu3+ doping led to an increase of Sn2+ and oxygen vacancies in SrSnO3 lattice, playing an essential role in the antibacterial activity. Reduced Eu2+ species were also observed The samples had activity below 5 % against Escherichia coli, whereas (SrEu)SnO3 displayed an efficiency of 100 % after 24 h against Staphylococcus aureus at a concentration of 1 mg/mL. Our results demonstrate that a specific chem. doping with Eu induces the formation of distinct point defect (Sn2+, Eu2+ and V•O) in the materials, which promoted a neg. surface charge that seems to have improved the redox ability and, therefore, enhanced the biocide property.