Abstract: The combinational probes of ultrasonic detection of longitudinal and circumferential flaws in the oil pipe tube side were introduced, including its technical background, theoretical basis, practical implementation and practical applications. Longitudinal-wave direct probe and variable angle transverse-wave probe using organic glass wedge were employed to proceed longitudinal and circumferential flaw detection, respectively. The combination probes can complete tube-side longitudinal and circumferential flaw detection at the same time.