Abstract: By using the model of pseudo-three-dimensional pressure drawdown analysis, and introducing filtration height with the comprehensive consideration of the stress difference between reservoir and the upper and lower interlayer for formation actual situation and accurate parameter interpretation. The mathematical fitting method can calculate fitting pressure and closure pressure so that pressure drawdown analysis interpretation is simple, direct and accurate. The Visual Basic6. 0 program can make corresponding explanation program.  So the site study verifies the correctness of the model and the rationality of the program.