Despite advances in understanding the complexities of acute myeloid leukaemia (AML), the treatment of refractory or relapsed AML (rrAML) remains a daunting clinical challenge.The investigators designed a new regimen, including chidamide, decitabine, aclarubincin, cytarabine and G-CSF, to treat rrAML.

Inclusion Criteria:

• Men and women whose age more than 18 and less than 59；
• Patients diagnosed as AML according to the 2008 WHO (WHO) myeloid malignant disease diagnosis standard;
• Patients who relapsed after remission or who can not achieve remission after at least two cycle of systemic therapy (including chemotherapy, hematopoietic stem cell transplantation, etc.);
• ECOG performance status 0-3;
• Expected survival time ˃ 3 months;
• Patients without serious hearts, lung, liver, kidney disease;
• Patients have not received radiotherapy, chemotherapy, targeted therapy or hematopoietic stem cell transplantation and other treatment within 4 weeks prior to the enrollment;
• Patients are able to understand and willing to sign informed consent.

Exclusion Criteria:

• Patients who allergy to the study drug or the drug with similar chemical structure;;
• Pregnancy, lactation women and women of childbearing age who do not want to practice effective methods of contraception;
• Active infection;
• Drug abuse, long-term alcohol abuse so as to affect the results of the evaluation of patients;
• Patients with mental disorders or other conditions can not obtain informed consent, can not meet the requirements of the study treatment and procedures;
• Patients have clinical significant QTc interval prolongation history (male > 450ms. Female >470ms), ventricular heart had tachycardia (VT) and atrial fibrillation (AF), II degree heart block, myocardial infarction attack (MI) within 1 year prior to the enrollment, congestive heart failure (CHF), patients of coronary heart disease who have clinical symptoms and need drug treatment.
• Cardiac ultrasound showed that the diastolic pericardial fluid dark area width ˃ 10mm;
• Patients have received organ transplantation;
• Active bleeding
• Patients have new thrombosis, embolism, cerebral hemorrhage and other diseases or medical history of patients within 1 year prior to enrollment;
• The main organs of the surgery is less than 6 weeks;
• Bone marrow hyperplasia and WBC <2.0 * 10^9/L;
• Liver function abnormalities (total bilirubin > 1.5 times of upper limit of normal range , ALT / AST > 2.5 times of the upper limit of normal range or patients with liver involvement whose ALT / AST > 1.5 times of upper limit of normal range), renal anomalies (serum creatinine > 1.5 times of upper limit of normal value );
• Not suitable for the study according to investigator's assessment.