The invention relates to a copper alloy conducting bar and an end ring for a high-power frequency-adjustable speed-adjustable asynchronous traction motor and preparation methods thereof. The conducting bar is prepared by the processes of medium-frequency induction melting, semi-continuous casting, ingot homogenization, hot extrusion, online quenching, cold drawing, aging and machining; and the end ring is prepared by the processes of medium-frequency induction melting, semi-continuous casting, ingot homogenization, forging, solid solution hardening, cold heading, aging and machining. The alloy of the conducting bar for a traction motor of a rapid train comprises the following components in percentage by weight: 9 to 12 percent of Zn, 0.3 to 1 percent of Cr, 0.05 to 0.3 percent of Zr and the balance of copper and inevitable impurities, wherein the resistance Rho at 150 DEG C of the alloy is kept at (5.00+/-0.05)*10<-6>ohm.cm, and at a test temperature of 350 DEG C, sb is more than or equal to 320MPa, s0.2 is more than or equal to 270 and d5 is more than or equal to 10 percent; the alloy of the conducting bar for the traction motors of subway and light rail trains comprises the following components: 0.5 to 3 percent of Zn, 0.3 to 1 percent of Cr, 0.05 to 0.3 percent of Zr and the balance of copper and inevitable impurities, wherein the resistance Rho at 150 DEG C of the alloy is kept at(3.45+/-0.05)*10<-6>ohm.cm, and at a test temperature of 350 DEG C, sb is more than or equal to 290MPa, S0.2 is more than or equal to 240MPa, and d5 is more than or equal to 12 percent; the copper alloy of the end ring for the traction motor comprises the following components: 0.3 to 1 percent of Cr, 0.05 to 0.3 percent of Zr and the balance of copper and inevitable impurities, wherein the resistance Rho at 150 DEG C of the copper alloy is kept at (2.70+/-0.05)*10<-6>ohm.cm, and at a test temperature of 350 DEG C, sb is more than or equal to 260MPa, s0.2 is more than or equal to 220MPa.