Retinoblastoma is the most common primary intraocular tumor in childhood. Diffuse anterior retinoblastoma is an uncommon variant and usually occurs in comparatively older children. Typically, there is an extensive infiltration of the anterior segment by tumor cells clinically mimicking anterior uveitis with pseudohypopyon. The actual retinal focus is often very small and may not be detected despite a thorough histological examination. In this case report the clinical and histological findings of a diffuse anterior retinoblastoma are described.