Joubert syndrome (JS) is a rare, complex autosomal or X-linked recessive inherited disorder mostly characterized by partial or complete agenesis of the cerebellar vermis. There is a wide clinical and genetic heterogeneity in the syndrome. The main clinical features of JS are hypotonia, ataxia, developmental delay, oculomotor apraxia, breathing abnormalities and peculiar neuroimaging findings. A lot of additional features have been reported. Here, we first reported a case of the syndrome with natural killer(NK) cells deficiency. To date, nearly all JS genes identified encode for proteins expressed in the primary cilium and/or basal body and centrosome, making JS part of the expanding group of ciliopathies. We review clinical features and molecular genetics of Joubert syndrome.