Stimulus equivalence demonstrates untrained stimulus-stimulus relations that emerge from stimulus-stimulus training (Sidman, 1971). His research proved to be influential in basic and applied research in a many areas such as reading, language arts, and mathematics; however little research exists on using stimulus equivalence training to teach a second language to children with Autism. The current study uses stimulus equivalence to teach a second language, to a child with Autism in order for her to communicate with her monolingual parents. The participant is a 7-year old girl diagnosed with Autism who primarily communicates in English. A pre-test was administered to determine Spanish-vocabulary baseline. During baseline, the participant demonstrated the use of only two Spanish words. Parents were surveyed to determine which Spanish words would be used most commonly in the natural context. Sixty words were identified and categorized into six subsets: numbers, foods, actions, emotions, clothing items, and essential household items. Participant was directly tested to show the trained relations in the presence of an auditory stimulus. In Phase 1, the participant was trained from the spoken word in English (A) to the picture of the word (B). In Phase 2, the participant was trained from the spoken word in English (A) to the written word in English (C). In Phase 3, the participant was trained from the spoken word in English (A) to the spoken word in Spanish (D). Once the participant demonstrated acquisition of the Spanish word based on mastery criteria, new words were then introduced. The results of using stimulus equivalence to teaching a second language to children with Autism are useful and promising. The participant expressively states her age, date of birth, address, and telephone number in Spanish upon request in the presence of her parents. Limitations and future research should include training more children, training children of different ages, and/or using stimulus equivalence to teach another language other than Spanish.