The invention discloses lock body steel easy to drill and fast in chip removal and a preparation method thereof, and belongs to the technical field of locks. The steel comprises the following chemical components in percentage by mass of 0.01-0.03% of C, 0-0.04% of Si, 1.6%-2.0% of Mn, 0.010%-0.030% of P, 0.40%-0.55% of S, 0.15%-0.22% of Bi, 0.005%-0.01% of Se, 0.003%-0.006% of T[O], 0.004%-0.006% of B and the balance of Fe and inevitable impurities. According to the steel, a certain amount of Bi and Se are compositely added, and the content of Mn and S in the steel is optimized, so that the sizes and forms of Mn (S, Se), ferrite and pearlite of the lock body steel are effectively controlled, the hardness of the steel is further reduced, the chip removal and breaking capabilities in the drilling process of the steel are improved, and the service life of a drill bit is prolonged; and in the preparation process, through forging, hot rolling, staged cooling and shot blasting processes, a lock body steel product with a matrix ferritic structure, a small amount of pearlite structures and excellent drilling performance is finally obtained, and the product is low in hardness, easy to drill, fast in chip removal, fast in heat dissipation and small in abrasion to a high-speed drill bit and can be widely used for manufacturing padlocks and calabash lock bodies.