A state of biochemical hypothyroidism is commonly seen in infants with congenital nephrotic syndrome (NS) and therefore the current recommendation is to place all patients with congenital NS on supplemental thyroid preparations. We report our experience in five children with congenital NS in whom thyroid supplementation was discontinued following bilateral nephrectomy and initiation of renal replacement therapy. Immediately after nephrectomy, thyroid function tests normalized, except serum thyroid-stimulating hormone (TSH) concentration, which initially rose, but normalized later. This observation supports the hypothesis that hypothyroidism in these patients is secondary to the chronic massive proteinuria and is not the result of a defect intrinsic to the thyroid gland itself. Abatement of massive proteinuria enables discontinuation of thyroid supplementation, and a transient rise in TSH in the early post-nephrectomy stage should be potentially expected.