The performance of devices based on two-dimensional (2D) materials is fundamentally limited by their contacts with metal electrodes. Thus, the realization of covalent bonding between 2D materials and metal electrode presents a potential solution. Here, we fabricate a novel type of interface between 2D boron sheet (borophene) with one-dimensional (1D) silver chains on Ag(111) surface. Using scanning tunneling microscopy (STM) and density functional theory (DFT), the atomic structures of the boron-silver interface are identified, which indicate 4-fold superlattice modulation with a period of ∼1.20 nm along the borophene edges due to the compressive strain field at the interface. Electronic structure analysis reveals charge transfer and the formation of polar covalent Ag-B bonds at the interface, facilitating efficient electron injection reminiscent of an Ohmic contact. This work establishes a substrate-enabled, stress-driven pathway for creating atomically precise 2D materials/metal interfaces, providing a model platform for exploring low-dimensional quantum phases and the fundamental interface engineering.