Objective: To investigate the prevalence of heterophoria among urban and rural students in Shantou 
City of Guangdong Province, China. Methods: Cluster sampling was used in randomly selecting 7 537 
students from 9 schools in Shantou City. Ocular alignment was assessed by using the Hirschberg light 
reflex and cover test. Cover testing was performed by using fixation targets at both distance (6 m) and near 
(30 cm). Statistical analyses were performed using SPSS statistical software to investigate the association of 
age, grades and schools and different types of strabismus. Results: A total of 7 464 students were examined  (participation rate was 99.03%), including 3 928 boys and 3 536 girls, mean age 11 years. The prevalence of 
esophoria and exophoria were3.08% and 60.65%. Esophoria prevalence of primary school students have the 
signiffcant difference (P<0.001) contrast with middle school students and high school students. And prevalence 
of exophoria was highest in high school students and significantly higher than middle and primary school 
students respectively (P<0.001). Heterophoria was more prevalent in rural school students than urban school 
students(P<0.05). Multivariate logistic regression model indicated that the prevalence of heterophoria had no 
significant correlation with grades and ages. Conclusion: This survey first reported the prevalence of heterophoria 
in China. The prevalence of esophoria appears to be higher in primary students and exophoria was highest in high 
school students; Prevalence of Heterophoria in the population of this survey generally showed higher in rural 
school students than urban areas. These may be associated with refraction in Chinese students.