The occurrence of visual loss in substantial numbers of adult patients with pseudotumor cerebri is well recognized. In children, the disease has been said to spare the visual system. We evaluated the ophthalmologic features of 36 children with pseudotumor cerebri followed up for one to 12 years. Four patients had rapid, severe loss of visual acuity and visual field changes while receiving medical therapy. Six others had less-severe but prominent abnormalities of visual acuity and/or visual fields at some point during the disease process. Only one patient had a permanent, severe visual impairment, but five had moderate permanent visual abnormalities. A severe degree of papilledema was seen only in the group with visual loss, but some patients in this group had only moderate papilledema. More patients with dural sinus thrombosis had serious visual loss than did those with other associated diseases or idiopathic pseudotumor cerebri. Quantitative perimetry of some sort can be performed in most children and is the preferred sequential test for planning treatment.