The purpose of this study was to examine the nature of substitution errors in typically developing Spanish-speaking children and those with phonological disorders. Previous research with Englishspeaking children has indicated that the frequency and types of substitution errors are two types of information that speech-language pathologists can use to differentially diagnose phonological disorders. In addition, previous studies with Italian speakers [Bortolini, U., & Leonard, L. (1991). The speech of phonologically disordered children acquiring Italian. Clinical Linguisitcs & Phonetics, 5, 1 -12.] and Portuguese speakers [Yavaş, M., & Lamprecht, R. (1988). Processes and intelligibility in disordered phonology. Clinical Linguistics and Phonetics, 2, 329 -345.] have indicated that substitution errors differ based on ambient language. No study has examined this phenomenon in Spanishspeaking children. In the current study, frequency and types of substitution errors in 39 typically developing children were compared to those in 39 age-matched children with phonological disorders. For both singletons and consonant clusters, typically developing children utilized a smaller number of substitutes per target, used a single substitute for a smaller number of targets, and exhibited dissimilar substitution patterns compared to their peers with phonological disorders. Some specific substitutions types were different than those reported for English-speaking children, indicating a language-specific pattern. These results have implications for the identification of Spanish-speaking children with phonological disorders and the cross-linguistic and language-specific nature of substitution errors.