Abstract: In low-permeability gas reservoir，reservoir pressure decline causes irreversible permeability damages as well as
the productivity impairment due mostly to the great lithologic compaction high flow resistance and poor pressure conductivity.
At present，the permeability stress sensitivity is evaluated by lab physical simulation experiment. This paper takes Longshen
low permeable gas reservoir of Jilin Oilfield as research subject. Based on the experimental research，this paper studies the
rock hardness，fracture distribution，clay mineral content and water saturation，and understands the stress sensitivity and rock
deformation mechanism of low permeable gas reservoir. The results show that Longshen gas field have strong stress sensitivity
and the reason of the phenomenon is that rock of the field have stronger clay grounting. That is high content of clay minerals
is the main reason of stress sensitivity. Forming a deformation mechanism regularity understanding of Reservoir. In order
to reduce the harm of stress sensitivity，the fracturing fluid of reducing the swelling of the clay minerals has been applied
to fracturing and we have optimized the reasonable production pressure difference，and got the desired results. The results
provided a powerful theoretical support for establishing the reasonable development techniques of this type of gas reservoir and
gas reservoir protection.

Key words: low permeable gas reservoir, stress, sensitivity, fracture, deformation mechanism