Yes.  In fact, mental illness can form one of the strongest basis for approving a Social Security Disability claim.  Imagine a clinically documented case of Agoraphobia in which the patient is terrified of leaving his or her house.  Or, imagine a case of bipolar disorder where the patient is so depressed that he or she does not get out of bed and doesn’t even eat for several days at a time.  Learn more about Disability with Mental Disorders here.