To compare the effects and safety of Anlotinib with placebo in patients with small cell lung cancer(SCLC).

Inclusion Criteria:

• Histological documentation of small cell lung cancer
• Advanced small cell lung cancer who had at least two chemotherapy regimens,at least one measurable lesion (by RECIST1.1)
• 18-75 years,ECOG PS:0-2,Life expectancy of more than 3 months
• Main organs function is normal
• Women of childbearing potential should agree to use and utilize an adequate method of contraception (such as intrauterine device，contraceptive and condom) throughout treatment and for at least 6 months after study is stopped；the result of serum or urine pregnancy test should be negative within 7 days prior to study enrollment，and the patients required to be non-lactating；Man participants should agree to use and utilize an adequate method of contraception throughout treatment and for at least 6 months after study is stopped
• Patients should participate in the study voluntarily and sign informed consent

Exclusion Criteria:

• Patients who have been used anlotinib

• Patients who have been used targeted drugs(such as sunitinib,bevacizumab,endostar),Immune targeted drugs

• 4 weeks or less from the last cytotoxic therapy, radiation therapy or surgery

• Patients whose primary lesion with active bleeding within 4 months

• Carcinomatous meningitis

• Patients who known to the central nervous system

• Patients with factors that could affect oral medication (such as dysphagia，chronic diarrhea, intestinal obstruction etc.)

• Patients with any severe and/or unable to control diseases，including：

  1. Blood pressure unable to be controlled ideally(systolic pressure≥150 mmHg，diastolic pressure≥100 mmHg);
  2. Patients with Grade 1 or higher myocardial ischemia, myocardial infarction or malignant arrhythmias(including QTc≥450ms(male),QTc≥470ms（female）) and patients with Grade 1 or higher congestive heart failure (NYHA Classification);
  3. Patients with active or unable to control serious infections;
  4. Patients with cirrhosis, decompensated liver disease, or active hepatitis;
  5. Patients with poorly controlled diabetes (fasting blood glucose(FBG)>10mmol/L)
  6. Urine protein ≥ ++，and 24-hour urinary protein excretion>1.0 g confirmed;

• Patients with non-healing wounds or fractures

• Patients with arterial or venous thromboembolic events occurred within 6 months, such as cerebrovascular accident (including transient ischemic attack), deep vein thrombosis and pulmonary embolism

• Patients with drug abuse history and unable to get rid of or Patients with mental disorders

• Imaging showed tumors have involved important blood vessels or by investigators determine likely during the follow-up study and cause fatal hemorrhage

• History of immunodeficiency

• Patients with concomitant diseases which could seriously endanger their own safety or could affect completion of the study according to investigators' judgment