Racial and ethnic disparities in service utilization in autism are widely documented. Autism-related parental stigma may play a role if parents from racial/ethnic minoritized backgrounds experience dual stigma from autism and from membership in a marginalized group. This study examines racial/ethnic differences in autism-related stigma and compares the impact of stigma on service utilization in a large, diverse sample of US-based parents of autistic children (final sample = 764; White 41.6%, Black 16.6%, Latino/a/x/Hispanic 20.9%, Asian 7.5%, Multiracial 9.6%, Native American 1.8%, Pacific Islander 0.5%, Middle Eastern 0.2%, and Other 0.2%). Parents completed online surveys assessing affiliate and community stigma, service utilization, and perceived unmet treatment needs. Small but significant racial/ethnic group differences emerged in some aspects of stigma and service utilization. Specifically, Asian and Latino/a/x parents were less likely to fully engage in recommended services; Asian parents endorsed less service availability; Latino/a/x and multiracial parents reported more unmet needs; and Asian and White parents reported significantly more affiliate stigma. There was little indication that stigma contributed to racial/ethnic differences in service utilization, except for Asian families. Results indicate that socioeconomic factors interact with race/ethnicity to impact service use and stigma.