Pulmonary infection after a tsunami is often polymicrobial and tends to form chronic pyogenic lung disease, necrotizing pneumonia, and empyemas. We report a combined pulmonary infection of Legionella and multiple antibiotic-resistant Escherichia coli in a previously well 75-year-old woman following immersion in tsunami waters 1 km inland from the Pacific coastline following the Tohoku Region Pacific Coast Earthquake of 2011. She needed drainage several times and the long-term use of multiple antibiotics according to the type of bacteria found and antibiotic susceptibility. We should be mindful of infections caused by multiple pathogens in the environment in Japan as a consequence of a tsunami disaster.