Anti-streptococcal O is an anti-streptococcal hemolysin “O”. How long it takes for a high anti-streptococcal hemolysin “O” to return to normal is not generalized, and it may take from three months to a year to return to normal, or from six months to a year to return to normal. Anti-streptococcal hemolysin “O” is an antibody, and its elevation suggests a previous streptococcal infection. The time it takes for anti-streptococcal hemolysin “O” to return to normal after being elevated depends on the situation. If it is mildly elevated, without fever, sore throat, swollen joints and other clinical manifestations, it can be treated with antibiotics as prescribed by the doctor, such as injection of benzylpenicillin, and the anti-streptococcal hemolysin “O” will usually return to normal after three months or half a year. If there are abnormalities in other indicators, it is necessary to go to the hospital to investigate rheumatic heart disease or rheumatoid arthritis, etc. Through standardized treatment for half a year to one year, the anti-streptococcal hemolysin “O” can usually be reduced to normal. If the patient has a high anti-streptococcal hemolysin “O”, it is recommended to consult a doctor in time to identify the cause of the disease, and under the guidance of the doctor according to the cause of targeted treatment.