Odón de Buen y del Cos (1863 in Zuera, Zaragoza Province, Aragon, Spain – 1945 in Mexico City) was a Spanish naturalist, politician and publicist. He founded the Spanish Institute of Oceanography, and was a senator and council-member in Barcelona.
Born to a tailor, de Buen studied Natural History in Madrid and Zaragoza. He became interested in oceanography after doing research on board of the Blanca fragatta. From 1889 to 1911 he taught zoology and botany at the University of Barcelona. On board of the Averroes, he studied the currents by Gibraltar. The acclimation of the Gambusia affinis, a larva-eating fish used to combat malaria is attributed to his son, parasitologist Sadí de Buen Lozano.
In 1939, like many scientists, artists and intellectuals, he left Spain for Mexico in the aftermath of the Spanish Civil War. He died in Mexico City in 1945.
- De Kristiania a Tuggurt (1887)