Little is known about age-related cognitive differences in autism spectrum disorder (ASD). However, given the overlap in cognitive impairments in ASD to those seen in typical aging, it is possible that adults with ASD will face even greater cognitive difficulties as they age. The current study used a cross-sectional design to examine age-related cognitive differences in adults with ASD and age and IQ-matched adults with typical development (age range 30-67 years). Results indicated that both age and diagnosis were related to poorer cognitive performance. However, adults with ASD exhibited pronounced age effects on measures related to executive functioning compared to adults with typical development, suggesting that aging in ASD may disproportionately affect specific cognitive processes.