Objective  To study the body image perception among pupils and their parents in Guangzhou city of Guangdong province, and to provide evidences for effective intervention on childhood obesity.

  Methods  A questionnaire survey on body image perception and on-site height and weight measurement were conducted among 6 068 pupils of grade 3 to 5 and their parents from April to October 2014.

  Results  Among the pupils, the proportion of thin, overweight, and obesity were 14.49 %, 9.54 %, and 5.37 %; 77.85 % of the pupils were not satisfied with their body image, which was higher than their parents’ perception (72.98 %). The body dissatisfaction (BD) score of the pupils was 0.19 but the BD score of the parents for their children was – 0.30. Regardless of gender and grade, the BD score of the pupils was positive, while the BD score of the parents for their children was negative. Of the parents not satisfied with the body image of their children with normal weight, 70.01 % reported the expectation for their children to gain weight; whereas, of the pupils with normal weight but not satisfied with body image, only 46.07% reported the expectation to gain weight. Compared to the pupils of grade 3, more students of grade 4 and 5 expected to become thinner. More parents of senior grade pupils expected their children to gain weight than the parents of junior grade pupils. The pupils in public schools and their parents showed higher accuracy for body image perception than the pupils in private schools and their parents.

  Conclusion  Obvious bias exists in body image perception of grade 3 to 5 pupils and their parents and how to improve the accuracy of body image perception among pupils and their parents may be worthy of research for intervention on childhood obesity.