Cylindrical imploding shock waves were produced by detonating cylindrical explosive shells. TheZ‐pinch discharge was applied to the additive compression of imploding plasmas. Pulsive electric current was supplied through the axis of imploding plasmas at the instant of focusing. An additional rise of temperature of 50–100% was achieved. It might then be concluded that the additive compression of imploding shock plasmas is attained by the application of theZ‐pinch discharge.