ABSTRACT Both bilingualism and autism spectrum disorder (ASD) are growing more prevalent at a steady rate, highlighting the urgent need to identify bilingualism's contribution to the language skills of autistic children. Autistic children might be misdiagnosed as having a language impairment or be at risk of having their language difficulties attributed to bilingualism, hence delaying the attainability of appropriate services. Backgrounds with multiple risk factors such as low SES, parental educational level, and unfavorable cultural perceptions might add difficulties to bilingual autistic children's language development. Research demonstrates similar language development patterns in autistic bilingual and their monolingual peers; however, it highlights the lack of understanding of their language abilities compared to typically developing (TD) bilingual children. Most studies to date have been conducted among preschool-aged children, using only the dominant language; moreover, they have lacked comparison to control groups of TD children and have tended to favor middle- to high-SES families. To address these gaps, the broad objective of this research is to evaluate the contribution of different predictors of language skills development in bilingual autistic school-aged children. The first study will develop an adaptation of the research materials and recruitment strategies to achieve cultural and linguistic competence, with parents and community stakeholders as informants of the process. The second study will compare structural language skills in bilingual and monolingual autistic children and age-, gender-, and IQ-matched TD children and determine the relationships of these skills to sociodemographic, clinical, and cultural factors. The third study will compare perceptions of the value of bilingualism among parents of school-aged autistic and TD children to identify whether the interplay of parental perceptions, diagnoses, and other sociodemographic characteristics act as facilitators or barriers to the language development of bilingual autistic children. Applied thematic analysis will guide the adaptation process to offer a systematic method to maximize accessibility, feasibility, and acceptability of the research project. For the other two studies, multivariate analysis of variance (MANOVA) and multiple linear regression analyses will examine the effects of the potential predictors on the language skills of bilingual autistic children. The proposed study will (1) advance our understanding of the interaction of bilingualism and language abilities in autistic children and (2) potentially inform standards for language assessments for Spanish-English speaking bilingual autistic children. The expected results will lay the foundation for an R01 study of bilingual autistic children's specific characteristics related to better outcomes. Our proposal aligns with the strategic plan of the NICD's mission by identifying clinical, linguistic, and demographi...