Gifted children with autism spectrum disorder (ASD) are often referred to as twice-exceptional, the term that highlights the co-occurrence of exceptional challenges and exceptional giftedness. This study performed secondary data analysis on samples of twice-exceptional children from the Pre-Elementary Education Longitudinal Study and the Special Education Elementary Longitudinal Study datasets. The results provide a descriptive profile of twice-exceptional (e.g. demographics, average academic performance, and services utilized), trajectory plots that indicate how academic performance changes over time, and multilevel analyses that model growth in academic outcomes using demographics, school services, and giftedness as predictors. Some of the key findings are that twice-exceptional students show not only higher initial levels of academic performance, but they improve over time relative to the non-gifted ASD counterparts and--with the exception of Letter Word Matching--even relative to the general population. Moreover, they benefit from mental health services disproportionately. Together, the results offer a deeper understanding of the twice-exceptional autistic population, their academic performance over time, and the services that they utilize.