Objective To investigate the effects and mechanisms of anlotinib in reversing bevacizumab resistance in lung adenocarcinoma. Methods Bevacizumab-resistant cell lines were established using human lung adenocarcinoma A549 and NCI-H1299 cells. Experimental groups included: bevacizumab-resistant A549 cells (Res-A549), Res-A549+bevacizumab, Res-A549+anlotinib, Res-A549+combination therapy; bevacizumab-resistant NCI-H1299 cells (Res-H1299), Res-H1299+bevacizumab, Res-H1299+anlotinib, and Res-H1299+combination therapy. Cell proliferation, viability, and invasion were assessed via EdU assay, MTT assay, and Transwell chamber assay, respectively. qRT-PCR and Western blot were performed to evaluate mRNA and protein expression of RGCC, CDH2, MMP2, and SERF1A. Results Compared with parental A549 cells, bevacizumab-resistant A549 cells exhibited significantly enhanced proliferative activity (P<0.05). Similarly, Res-H1299 cells showed markedly increased proliferation versus parental NCI-H1299 cells (P<0.05). Anlotinib treatment significantly reduced viability and invasive capacity in Res-A549 cells compared with Res-A549 controls (P<0.05). The combination therapy demonstrated stronger inhibitory effects on these parameters than either bevacizumab or anlotinib monotherapy (P<0.05). Consistent with A549 findings, Res-H1299 cells treated with anlotinib exhibited significantly decreased viability and invasion versus Res-H1299 controls (P<0.05), while the combination group showed superior efficacy compared to both monotherapy groups (P<0.05). In Res-A549 cells, bevacizumab monotherapy upregulated mRNA levels of RGCC, CDH2, MMP2, and SERF1A compared with Res-A549 controls (P<0.05). Conversely, anlotinib treatment downregulated both mRNA and protein expression of these markers (P<0.05). The combination therapy further reduced their expression relative to bevacizumab monotherapy (P<0.05). Parallel results were observed in Res-H1299 cells: Bevacizumab increased mRNA and protein expression of all four targets (P<0.05), whereas anlotinib suppressed their expression (P<0.05). The combination group showed significantly lower expression levels compared to bevacizumab-treated Res-H1299 cells. Conclusion Anlotinib reverses bevacizumab resistance in lung adenocarcinoma by suppressing RGCC, CDH2, MMP2, and SERF1A expression, thereby enhancing antitumor efficacy