The veracity of the sounding data and weather forecasts would be influenced if the sounding instrument was degenerated. The sounding data, such as the height and meteorological elements of the isobaric surface, the ascending velocity of the balloon, and altitude difference profiles, are analyzed. The characteristics of different sounding instrument degeneration and discrimination methods are summarized. Using the method of absolute error calculation and intensive meteorological element calculation, combined with graphics, data comparison, the time to change for induction curves can be determined. Thus the sounding data can be treated timely and effectively, and the quality of the sounding data can be improved.