The utility model relates to a novel threaded-connection petroleum drill rod joint with double shoulders, which comprises a male thread joint (1) and a female thread joint (2) and is characterized in that a male joint auxiliary torque shoulder (7) and a female joint auxiliary torque shoulder (8) are respectively arranged at the bottoms of the male thread joint (1) and the female thread joint (2); the axial length of a lengthened surface at the bottom of the male joint is up to 46 mm, and the axial length of a lengthened surface at the bottom of the female joint is up to 48 mm; both the male thread and the female thread adopt taper thread with taper of 1:8; and the radius (R1) of a tooth-shaped low circular arc of the male thread is up to 1 mm and the radius (R2) of a tooth-shaped high circular arc of the female thread is up to 1mm. According to the utility model, the torsional strength and fatigue strength of the petroleum drill rod joint are greatly improved, and at the same time, the phenomena of thread gluing and swelling are obviously reduced.