Patients with bipolar disorder mainly show hyperactive or easily provoked mood, increased speech and activity, and high energy during mild manic or manic episodes. As for sleep, it is common that the need for sleep is reduced, and only 3-4 hours of sleep per night is sufficient to remain refreshed during the day. However, some patients with bipolar disorder show strange periodic cycles of sleep, but rarely attract the attention of patients, often leading to delayed consultation. Case 1: A 37-year-old woman came to the clinic with the main symptom of “sleeplessness (insomnia) 1/3 of the month, sleeplessness (narcolepsy) 1/3 of the month, and normal sleep 1/3 of the month”. After careful questioning, the patient recalled that for many years he felt emotionally “hyper” during insomnia, energetic, active and productive, while during narcolepsy he was depressed, bedridden and reluctant to go out, and often took sick leave to rest. The patient did not pay attention to this cycle for years and years, but was not treated until advised by a colleague who was ill. This patient is currently considering pregnancy, but now has to complete treatment before she can consider pregnancy. If she had realized early that she needed to be seen for sleep abnormalities, she could have completed her treatment cycle sooner and not delayed her pregnancy planning at an advanced age. Case 2: Another young 25-year-old male recalled that he had a cyclical sleep cycle since junior high school, with a general pattern of “low mood (insomnia) – “high mood” (normal sleep) – normal mood. –The pattern was roughly “mood depression (insomnia) – mood “arousal” (normal sleep)”, but he did not pay attention to it and continued for many years until his condition worsened and then he was seen. Case 3: A middle-aged female patient in her 60s, who has suffered from bipolar disorder for decades and has been taking mood stabilizers for years, still feels that she is prone to “depression” only in spring, autumn and winter, while denying that she has a (mild) manic problem. The patient can clearly describe his performance during depression: “I can’t get up, I don’t want to move, I don’t want to talk, I can sleep for several days in a row, I have no energy, and it’s difficult to go to the doctor”; while he thinks “it’s normal, I’m quite happy” during his mild manic episode. The only change I admit is that I can get up and don’t need to sleep so much anymore. It can be seen that the above-mentioned bipolar disorder patients all have sleep abnormalities when their condition fluctuates, however, the patients tend to ignore their mood changes and only notice the changes in sleep form or quality. For a part of patients who do not realize that their (mild) manic performance is abnormal, if they can seek timely consultation for sleep reasons, it will provide valuable opportunities for timely treatment. It is recommended that patients or family members who find themselves or their loved ones in a similar situation should go to a psychiatric hospital for consultation in a timely manner and be highly alert to whether they are suffering from “bipolar disorder”.