The current study, with 409 fourth graders in two-way immersion programs, explored the writing self-perceptions of native English and native Spanish speakers and the relationship between self-perceptions and writing performance. An adapted version of the Writer Self-Perception Scale (WSPS) was administered along with a writing task. Native English speakers reported higher English writing self-perceptions than native Spanish speakers. However, native Spanish speakers did not report consistently higher Spanish writing self-perceptions than native English speakers. Regression analyses demonstrate positive associations between self-perceptions and performance in both languages. The present study supports the value of capturing students' writing self-perceptions in two languages.