This cross-sectional study aims to examine the age differences in state anxiety (i.e., anxiety triggered toward specific situations) as well as its relationship to the reading comprehension of Chinese students with and without dyslexia across school ages. In total, 131 typically developing students and 81 students with dyslexia in primary and secondary schools were recruited in Taiwan. Our results indicate that students with versus those without dyslexia have different patterns of state anxiety across the three age levels. In addition, we found similar patterns between students with dyslexia and those without across the three age levels in the effects of state anxiety on reading comprehension. However, the contributions of state anxiety to reading comprehension tended to decline as typically developing students matured, while they remained relatively constant for students with dyslexia across the three age levels. These results may have implications for teaching activities or examinations for students whose state anxiety has a significant impact on their reading comprehension skills.