Numerous studies have demonstrated an association between the acuity of the approximate number system (ANS) and mathematical performance. Moreover, studies have shown that ANS acuity can predict the longitudinal development of mathematical achievement. A recent novel explanation of this association is the visual form perception hypothesis (Zhou, Wei, Zhang, Cui, & Chen [2015]. Visual perception can account for the close relation between numerosity processing and computational fluency. Frontiers in Psychology, 6, 1364). The current study aimed to test whether the visual form perception could account for the ANS prediction for longitudinal development of mathematical achievement. One hundred and eighty-eight participants (100 males, 88 females, mean age = 12.2, SD = 0.3) took part in the study. When they were at third grade, they took the tests: numerosity comparison, figure matching as well as mental rotation, non-verbal matrix reasoning and choice reaction time.3-year later, they took mathematical achievement test. The results showed that the ANS acuity measured with numerosity comparison could predict mathematical achievement 3 years later. As expected, the scores on figure matching could account for the longitudinal prediction role of ANS acuity to mathematical achievement. The result further confirms the visual form perception is the underlying cognitive mechanism for the association between ANS acuity and mathematical achievement in the longitudinal development.