Although recent studies have shown that catatonia can occur in patients with autism spectrum disorders (ASDs), the overlap of the behavioral features between these disorders raises many diagnostic challenges. In fact, in clinical practice it is common to misinterpret catatonic symptoms, including mutism, stereotypic speech, repetitive behaviors, echolalia, posturing, mannerisms, purposeless agitation and rigidity, as features of ASDs. The current medical treatment algorithm for catatonia in ASDs recommends the use of benzodiazepines. Electroconvulsive therapy (ECT) is indicated when patients are unresponsive, or insufficiently responsive, to benzodiazepines. Other pharmacological options are also described for the treatment of catatonic patients resistant to benzodiazepines and ECT, and there is evidence for the effectiveness of a psychological treatment, co-occurring with medical treatments, in order to support the management of these patients. In this article we provide a summary of studies exploring catatonia in ASDs and our clinical experience in the management and treatment of this syndrome through the presentation of three brief case studies. Moreover, we review the mechanisms underlying symptoms of catatonia in ASDs, as well as the diagnostic challenges, providing an outline for the management and treatment of this syndrome in this clinical population.