Since autism diagnosis is directly linked to the availability of supportive services, identifying best practices for early diagnosis of autism has long been a concern of professionals and families. Meanwhile, studies show persistent racial disparities in autism diagnosis. Although numerous clinical diagnostic guidelines have been published, there is not enough discussion of diagnostic procedures through the lens of culturally diverse families. Purpose: This study focuses on the autism diagnostic experiences that Korean immigrant mothers had with their children. Methods: Eleven first-generation Korean-American mothers of children with autism were included in the study. The data was collected using semi-structured interviews in Korean. Results: The main five factors (i.e., cultural beliefs and values, language barriers, complex emotions, immigration and navigating systems, and facilitators and assets) that mainly influence the diagnosis process were identified through thematic analysis. Conclusion: Dynamics are interactive within and between the factors, influencing the entire diagnostic process by either delaying or facilitating the identification of a child's autism and the provision of treatment.