The invention relates to an oil and gas pipeline L360M hot-rolled steel coil with the low yield ratio and a preparation method of the oil and gas pipeline L360M hot-rolled steel coil. The hot-rolled steel coil is prepared from the chemical components in percentage by mass: 0.05-0.09% of C, 0.15-0.30% of Si, 1.10-1.25% of Mn, less than or equal to 0.025% of P, less than or equal to 0.010% of S, 0.008-0.030% of Nb, and the balance of Fe and unavoidable impurities. According to the oil and gas pipeline L360M hot-rolled steel coil with the low yield ratio and the preparation method of the oil andgas pipeline L360M hot-rolled steel coil, by decreasing the contents of C and Mn in the components of oil and gas pipeline L360M steel, trace niobium microalloying is conducted, a suitable rolling process and a suitable cooling control process are adopted, the yield ratio is decreased, the comprehensive performance of steel is improved, the L360M hot-rolled steel coil with the low cost and high quality is produced, and energy conservation and emission reduction and the green steel concept are achieved.