Oosterella is an extinct ammonoid cephalopod genus belonging to the family Oosterellidae. These fast-moving nektonic carnivores lived during the Cretaceous, from the upper Valanginian age to the lower Hauterivian age.
Fossils of species within this genus have been found in the Cretaceous sediments of Argentina, Austria, Colombia, Czech Republic, France, Hungary, Italy, Mexico, Morocco, Romania and Slovakia.