Inclusion Criteria:  Patients with locally advanced or metastatic non-small cell lung cancer (NSCLC) confirmed histologically or cytologically ; Patients confirmed as ALK positive (FISH or Ventana IHC or RT-PCR, NGS) in previous written reports.Disease progression after continuing treatment with prior second-generation ALK-TKI resistance (allowing crizotinib resistance) (as per RECIST 1.1); Maximum one chemotherapy is allowed;The interval between the last administration of second-generation ALK-TKI and the trial enrollment should be at least 7 days; Gender: both male and female;Age: ≥18 years old; physical status score was 0-2; survival ≥3 months; certain organ system functions (no blood transfusion or use of constituent blood within 14 days before test)； Asymptomatic CNS metastases that do not require treatment with steroids or anticonvulsants;If there is CNS metastasis, radiotherapy can be performed first, and no progress can be made after ≥28 days.Meningeal disease was not included in the group; Patients must have measurable lesions according to RECIST1.1 criteria; Willing and able to follow the trial and follow-up procedures; Able to understand the nature of the experiment and sign written informed consent voluntarily.  Exclusion Criteria:  Patients who had previously only used crizotinib or loratinib； Currently receiving other systemic anti-tumor treatments； history of malignancy other than lung cancer in the past 3 years (excluding cured basal cell tumor of the skin, early gastrointestinal [GI] tumor resected under endoscope, carcinoma in situ of the cervix)； Patients who participated in clinical trials of other investigational drugs within weeks prior to initial ensatinib administration； Major surgery or immunotherapy within 4 weeks prior to initial; dosing;Radiation therapy was received within 2 weeks prior to initial dosing； In the investigator's opinion, may increase the risk associated with study participation or may interfere with the interpretation of study results; Other conditions considered unsuitable for participation in the study by the investigator.