Abstract: Chemotherapyinduced nausea and vomiting is the most common gastrointestinal reaction of chemotherapy side effects， and also one of the important influential factors in chemotherapy compliance within tumor patients. Olanzapine is a widely-used atypical antipsychotics in psychiatric clinical pratice， which also has a ability to block many different antiemetic properties ossociated receptors. In recent years， olanzapine has been approved effectively in the prevention and treatment of chemotherapyinduced nausea and vomiting， with little adverse reaction and good tolerance. This paper summarizes the clnical progression on prevention and treatment of olanzapine in chemotherapy induced nausea and vomiting.