Subacute sclerosing panencephalitis (SSPE) is a rare slowly progressing neurological illness. Although patients with SSPE initially present with symptoms such as myoclonic jerks, cognitive decline, and personality/behavioral changes usually, rarely pure psychiatric symptoms (e.g., mania, psychosis, and catatonia) have also been reported during the initial course of the illness. We report an unusual case of an adolescent with SSPE presenting with prominent positive psychotic and catatonic symptoms with the absence of classical symptoms of SSPE in initial course of illness and further discussed the relevant literature.