Background: Docetaxel is a standard second line treatment in advanced NSCLC, but the treatment effect is limited. Previous studies, such as REVEL, demonstrated that anti angiogenic therapy combined with docetaxel had significantly therapeutic efficacy. Anlotinib is an oral multi target angiogenesis TKI targeting the VEGFR, FGFR, PDGFR and c Kit. The ALTER 0303 trial showed that anlotinib improved both PFS and OS in later-line treatment for advanced NSCLC, and this study aims to investigate the efficacy and safety of Anlotinib combined with docetaxel in second-line treatment in advanced non-small cell lung cancer (NSCLC). Methods: This is a single-center, single-arm clinical trial. A group of 30 patients of histologically or cytologically confirmed, locally advanced stage IIIB-IV NSCLC and with ECOG PS 0-1 were admitted to the Kaifeng Central Hospital Cancer Center. Patients who progressed after first-line treatment were treated with anlotinib (12 mg p.o., QD d1 to 14, q3w) combined with docetaxel (75mg/m², iv, QD, d1 to 14, q3w) as the second-line therapy. The primary endpoint was PFS. Secondary endpoints were OS, objective response rate (ORR), disease control rate (DCR) and safety. Results: A total of 30 patients were enrolled from October 2018 to April 2020. At data cutoff (Sept. 30, 2020), 30 patients were available for efficacy analysis. The median progression-free survival (mPFS) was 7.5 months (2.0-18.5). Among these patients, there was 1 CR, 9 PR, 15 SD, 5 PD, resulting in the ORR = 33.33% and the DCR = 83.33%. The Cox multivariate analysis showed that stage is an independent risk factor affecting prognosis (p= 0.003). The most common grade 3 AEs were leukopenia (23,3%), neutropenia (13.3%), hypertension (13.3%), which can be controlled, and no grade 4 or grade 5 AEs occurred. Conclusions: Second line anlotinib plus docetaxel showed clinical benefit in advanced NSCLC patients in terms of PFS, ORR and DCR, and the incidence of adverse reactions are tolerable. This combination might be a promising option for patients advanced NSCLC.