A blast treatment method of blasting ammunition provided with a warhead and a propulsion unit provided on the rear end of the warhead, the warhead having a bursting charge, and the propulsion unit having a propellant that imparts propulsion to the warhead, the method comprising: a first explosive arrangement step of arranging a first explosive for blasting the warhead at a position on the outside of the warhead; a second explosive arrangement step of arranging a plurality of explosive members including a second explosive for initiating the propellant at positions on the outside of the propulsion unit; a warhead blast step of initiating detonation of the first explosive to cause detonation of the first explosive, and by means of the detonation of the first explosive, causing detonation of the bursting charge, thereby blasting the warhead; and a propulsion unit treatment step of initiating detonation of the second explosive to cause detonation of the second explosive, and causing deflagration of the propellant of the propulsion unit by means of detonation of the second explosive, thereby performing combustion of the propulsion unit, wherein in the first explosive arrangement step, the first explosive is arranged at a position covering the periphery of the warhead such that a high-pressure field is generated on the periphery of the warhead due to the detonation of the first explosive, and the high-pressure field suppresses divergence of detonation energy of the bursting charge to outside of this high-pressure field; and in the second explosive arrangement step, the plurality of explosive members are arranged in mutually separated positions, such that, by enabling divergence of the combustion energy of the propellant from the positions between the explosive members in the propulsion unit treatment step executed after the second explosive arrangement step, the detonation of the propellant is suppressed. the method comprising: a first explosive arrangement step of arranging a first explosive for blasting the warhead at a position on the outside of the warhead; a second explosive arrangement step of arranging a plurality of explosive members including a second explosive for initiating the propellant at positions on the outside of the propulsion unit; a warhead blast step of initiating detonation of the first explosive to cause detonation of the first explosive, and by means of the detonation of the first explosive, causing detonation of the bursting charge, thereby blasting the warhead; and a propulsion unit treatment step of initiating detonation of the second explosive to cause detonation of the second explosive, and causing deflagration of the propellant of the propulsion unit by means of detonation of the second explosive, thereby performing combustion of the propulsion unit, wherein in the first explosive arrangement step, the first explosive is arranged at a position covering the periphery of the warhead such that a high-pressure field is generated on the periphery of the warhead due to the detonation of the first explosive, and the high-pressure field suppresses divergence of detonation energy of the bursting charge to outside of this high-pressure field; and in the second explosive arrangement step, the plurality of explosive members are arranged in mutually separated positions, such that, by enabling divergence of the combustion energy of the propellant from the positions between the explosive members in the propulsion unit treatment step executed after the second explosive arrangement step, the detonation of the propellant is suppressed. a first explosive arrangement step of arranging a first explosive for blasting the warhead at a position on the outside of the warhead; a second explosive arrangement step of arranging a plurality of explosive members including a second explosive for initiating the propellant at positions on the outside of the propulsion unit; a warhead blast step of initiating detonation of the first explosive to cause detonation of the first explosive, and by means of the detonation of the first explosive, causing detonation of the bursting charge, thereby blasting the warhead; and a propulsion unit treatment step of initiating detonation of the second explosive to cause detonation of the second explosive, and causing deflagration of the propellant of the propulsion unit by means of detonation of the second explosive, thereby performing combustion of the propulsion unit, wherein in the first explosive arrangement step, the first explosive is arranged at a position covering the periphery of the warhead such that a high-pressure field is generated on the periphery of the warhead due to the detonation of the first explosive, and the high-pressure field suppresses divergence of detonation energy of the bursting charge to outside of this high-pressure field; and in the second explosive arrangement step, the plurality of explosive members are arranged in mutually separated positions, such that, by enabling divergence of the combustion energy of the propellant from the positions between the explosive members in the propulsion unit treatment step executed after the second explosive arrangement step, the detonation of the propellant is suppressed.