Nerve aberrations and vascular lesions in the distal lower limbs are the etiological factors for diabetic foot ulcers (DFUs). This study aimed to understand the regulatory mechanism of angiogenesis in patients with DFU by examining lncRNA, as well as to explore effective targets for diagnosing and treating DFU. The serum levels of A1BG-AS1 and miR-214-3p and the predictive power of A1BG-AS1 for DFU were determined by quantitative PCR and ROC analysis. The correlation of A1BG-AS1 with clinical characteristics was examined using chi-square tests. The risk factors for DFU in patients with type 2 diabetes mellitus (T2DM) were identified using the logistic regression model. Furthermore, the binding sites of A1BG-AS1 and miR-214-3p were determined. Next, A1BG-AS1 interference plasmid and miR-214-3p inhibitor were co-transfected into high glucose-induced cells to investigate their effects on the expression of angiogenesis-related genes and cell proliferation. The A1BG-AS1 levels were upregulated, whereas the miR-214-3p levels were downregulated in patients with DFU. The upregulation of A1BG-AS1 was significantly associated with both blood glucose levels and ulcer grades. A1BG-AS1 served as a crucial biomarker for diagnosing DFU and evaluating the risk of DFU occurrence in patients with T2DM. Co-transfection experiments revealed that the inhibition of miR-214-3p effectively recovered the suppressive effects of A1BG-AS1 on angiogenesis-related gene expression, endothelial cell differentiation, and proliferation. The sponging effect of A1BG-AS1 on miR-214-3p impaired angiogenesis in patients with DFU. Thus, A1BG-AS1 is a potential therapeutic target for DFU.