Primary hyperparathyroidism (PHPT) is relatively uncommon in children, and skeletal deformities due to it are even rarer in this age group. Less than 20 such cases have been reported in the English literature. We describe a case series of three patients who presented with genu valgum deformity and were found to have primary hyperparathyroidism on further evaluation. The cases were primarily managed by removing the adenoma and later taken up for correction of the skeletal deformity. Genu valgum deformity in children can occur secondary to hyperparathyroidism due to a pubertal growth spurt.