The invention discloses a lead-core type explosive element and a basic detonator composed of the explosive element. The lead-core type explosive element comprises an inner tube, a lead core part and aloose ignition charge. The lead core part is positioned in the upper part of the inner tube, the loose ignition charge is positioned below the lead core part in the inner tube, the basic detonator comprises a metal tube shell, and a grain charge, a loose charge and a lead-core type explosive element are sequentially arranged in the metal tube shell from bottom to top, and a delay body, an electronic ignition element or a detonating tube are additionally arranged above the lead-core type explosive element. The basic detonator does not need a primary explosive, and the problems of potential safety hazard, environmental pollution and high cost of the primary explosive are solved. The special tube shell and inner tube are not required, and the assembly process is simple; the phenomenon that detonators explode incompletely during inverted initiation is eliminated; and therefore, the primary explosive-free basic detonator of the invention has the advantages of high reliability, simple quality control, safety, environmental protection, economy and practicality.