Abstract: To solve the difficulties in coal mine floor water inrush evaluation，on the basis of the servo-controlled permeability test of rock in the complete stress-strain process，we proposed the concept of rock expansion boundary anti-permeability strength，and established a theoretical evaluation model of floor water inrush．In the model，several factors，such as the floor aquifuge effective thickness，lithology，rock mass integrity，and expansion boundary anti-permeability strength were considered，and the taking values of all factors were described in detail．Taking the No.17 coal seam and 2702 working face in Yangcun coal mine，Yanzhou mining group as an example，it proves that the evaluation model based on the expansive boundary anti-permeability strength is feasible to evaluate the coal mine floor water inrush．

Key words: rock expansive boundary anti-permeability strength, floor water inrush, RQD, complete stress-strain servo-controlled test, permeability