<p>Early intervention is crucial for children with developmental delays. However, immigrant parents often face more difficulties in accessing early intervention services. The systematic review aims to synthesize extant studies on perceived and actual challenges and opportunities of immigrant parents have in the early intervention service access process. A comprehensive search on five electronic databases, along with a manual search of the first 10 pages on the Google Scholar search engine and a back-and-forth citation search, was performed to identify suitable records. After conducting a multi-stage screening process, thirty-three studies were included in the review. By employing the thematic analysis method developed by Braun and Clarke (2006), the review identified four core themes: three focused on the barriers that immigrant parents faced at the personal, service system, and sociocultural levels; one theme emphasized parent strengths and facilitators of access to early intervention services. The review identified unique barriers immigrant parents faced for their children’s evaluation and treatment. These barriers included limited language skills, cultural traditions and beliefs, reduced social support, and undocumented status. The review found factors, such as a bilingual professional, a bilingual coordinator, a skilled translator, a culturally aware and compassionate professional, support from family and friends, community and cultural groups, and religion were helpful for immigrant parents to seek support for their children. The review findings underscore the need of addressing barriers holistically while strengthening facilitators to promote equity in early intervention service access among immigrant parents.</p>