The mathematic model using the Marsh cone flow time of subsection to mark the rheological property of alkali activated carbonates-slag grouting pastes was studied,and the corresponding relation between the test results of the Marsh cone flow time of subsection and those of the rheometer was discussed by simple computing of model.The results show that the mathematic model of rheological parameter from the Marsh cone flow time of subsection and that from the test results of the rheometer is y=ax+b.