Abstract: The present invention relates to a high-hardenability, medium-carbon, low-alloy round steel for fasteners, the chemical constituents by mass percentage are as follows: C: 0.36˜0.44%, Si: 0.15˜0.40%, Mn: 0.80˜1.00%, Cr: 1.00˜1.15%, Mo: 0.05˜0.25%, Ni: 0.05˜0.25%, Cu: 0.05˜0.25%, Al: 0.015˜0.050%, B: 0.0010˜0.0050%, Ti: 0.020˜0.050%, the balance is Fe; the maximum diameter of the round steel is 65 mm. The manufacturing process are as follows: the raw materials are processed, in sequence, by converter smelting, LF refining, RH/VD degassing to obtain molten steel, feeding Ti wires and ferroboron, continuous casting, rolling into the bar, obtaining the quenched and tempered round steel after quenching and tempering treatment; the quenched and tempered round steel is able to be directly used in processing fasteners which meet ISO 898-1 standard for grade 10.9, such as bolts and the like.