Introduction. Laurence-Moon-Biedl (LMB) syndrome is a rare autosomal-recessive ciliopathy with manifold symptomatology. The cardinal clinical features include retinitis pigmentosa, obesity, intellectual delay, polydactyly/syndactyly, and hypogenitalism. In this paper, the authors report on three siblings with Laurence-Moon-Biedl syndrome associated with a probable pseudocycloid form of congenital nystagmus. Methods. This was a case study conducted at King Khaled Hospital. Results. The authors assert that the nystagmus in Laurence-Moon-Biedl syndrome is essentially similar to idiopathic motor-defect nystagmus and the nystagmus seen in optic nerve hypoplasia, ocular albinism, and bilateral opacities of the ocular media. Conclusion. The data support the previous hypothesis that there is a common brain stem motor abnormality in sensory-defect and motor-defect nystagmus.