As shale gas wells enter the depletion period, gas well producing becomes more and more difficult, and its costs gradually rise, which causes profitable development faces challenge. Currently, it is sual to set technical abandonment period for shale gas well at 20 years, and no in-depth research has been conducted on its economic abandonment year and economic limit production. Therefore, a model to evaluate the economic limit production of shale gas wells is constructed. First, it studys the operating cost rules of shale gas wells by dividing historic operating cost into fixed costs and variable costs. And then it develops an operating cost model to forecast cost at the end of period. Later an economic limit production evaluation model is established based on the break-even principle to measure the economic limit production of a single well and build a corresponding sensitivity chart to quantitatively evaluate a certain. At last, An analysis of technical and economic EUR for a certain shale gas field is made to summary the economic boundary characteristics of different sizes of EUR to provide a basis for future shale gas EUR evaluation.