Bipolar disorder and schizophrenia are both relatively common serious mental illnesses at present, but they are two completely different types of illnesses, with the following differences: 1. Patients with bipolar disorder and schizophrenia may both have emotional abnormalities. For example, patients with bipolar disorder are prone to anger and temper tantrums, while patients with schizophrenia may also have corresponding emotional abnormalities and be easily provoked. In contrast, however, emotional instability in patients with bipolar disorder may only occur during episodes of illness, i.e., patients with bipolar disorder have intermittent episodes of abnormal emotions. For schizophrenic patients, there is no remission period in the development of their illness, unless the schizophrenic patient receives professional treatment, and the schizophrenic patient in recovery can be in a stable mood; 2. Both bipolar disorder patients and schizophrenic patients may have some psychotic symptoms, but in comparison, the schizophrenic patient’s psychotic symptoms may be more ridiculous However, in comparison, schizophrenic patients may have more absurd, bizarre, and even positive psychotic symptoms such as hallucinations and delusions, while patients with bipolar disorder have exaggerated, delusional, and other partially psychotic symptoms that are coordinated with their moods, often secondary to high emotions; 3. However, the cognitive impairment is more severe in patients with schizophrenia compared to patients with bipolar disorder, i.e., with systematic treatment, patients with bipolar disorder may be able to recover or even be better than their premorbid state, but patients with schizophrenia have poorer recovery of social functioning compared to patients with bipolar disorder.