Objective   To explore the impact of parental myopia on their children′s risk of myopia and to provide evidences for developing measures on myopia prevention and control in school-age children.

  Methods  Using cluster random sampling, we recruited 3 433 students of grade 1 – 2 in 12 public primary schools in 2 districts of Guangzhou city. Visual acuity examination after mydriasis among the students and questionnaire survey on demographics and parental myopic conditions in the students′ parents were conducted during December 2018 and February 2019.

  Results   For the 3 172 students with complete information, the average length of eye axis was 22.9 ± 0.8 mm; the average equivalent spherical lens prescription was 0.9 ± 1.1 degree; and the overall prevalence rate of myopia was 7.5%. Compared to those with neither paternal nor maternal myopia, the students with both paternal and maternal myopia had a 2.5 times higher myopia prevalence rate (13.23% vs. 6.99%). The myopia prevalence rate of the students with paternal high myopia was significantly higher in comparison to that of students with maternal high myopia (24.7% vs. 16.6%, P < 0.001). After adjusting for students′ age, height and weight, the results of multivariate logistic regression analysis indicated that paternal and maternal myopia (adjusted odds ratio aOR = 2.72, 95% confidence interval 95% CI 1.96 – 3.78), paternal high myopia (aOR = 5.54, 95% CI: 3.31 – 9.26) and maternal high myopia (aOR = 3.10, 95% CI: 1.94 – 4.93) were significant risk factors for the students′ myopia; the results also showed that the students with paternal high myopia had a 1.8 times higher myopic risk than the students with maternal high myopia.

  Conclusion   Parental myopia and both paternal or maternal high myopia are important risk factors for myopia in school-age children.