This study was carried out to measure the flaw height of welds in consideration of the effective probe angle in ultrasonic oblique detection. Specimens with inserted artificial flaws were made and flaw heights were estimated from detecting these specimens. Two different methods were applied to estimate flaw heights. From the result of the experiment, flaw height could be measured within the accuracy of 15% percent error and the difference between the probe distance method and beam path method is about 5% relatively small. It is considered that the results obtained this experimental study could be helpful informal ions for measuring flaw height.