Abstract: The laboratorial experiment has been done and gotten much data of stress-sensitivity in low permeability formation. By analyzing and summing up to find, the data points plot on semi-log plot does not show a single linear but two or multiple stage linear curves. The theory of multiple stage variety for
stress-sensitivity has been put forward. These phenomena can be well characterized by two or multiple stages exponent formulation, then stress-sensitivity mathematical models of permeability variation at different stage and pseudo-steady gas well productivity forecast mathematical models by permeability exponent variation have been made. The stress-sensitivity characteristic has been analyzed in gas fields in Tarim Basin and its methods
of gas well productivity forecast have been given. Thetheory and methods have important instructional significance for highly efficiently exploitation of the low permeability stress-sensitivity formation.

Key words: stress-sensitivity, low permeability formation, gas well, productivity, prediction