Research on the second language (L2) acquisition of the Spanish copulas has been central to our understanding of key concepts and issues in the field of SLA such as stages of development and variability in L2s. However, this research has focused nearly exclusively on native English-speaking learners. The present study examined native Korean-speaking learners' acquisition and use of the Spanish copulas with adjectives in oral production. Analyses of the range and frequency of copula forms produced across four levels of Spanish language study revealed an increase in "ser" and "estar" use and a decrease in developmental omission as learner level increased. Predicate type, resultant state, and Spanish grammar score significantly influenced use of "estar" over "ser." Comparison with native English-speaking learners revealed differences between first language groups in terms of rates of form use, but similar developmental trends and predictors of "estar" use overall.