In high stress soft rock roadway， often with very serious floor heave， which has a great influence on production and construction of coal mine. In this paper， on the basis of the research results on floor heave at home and abroad， and the serious floor heave in +600 m main haulage roadway in a mine， the corresponding mechanical model was established to analyze the deformation mechanism. Then combining supporting effect of the original supporting scheme， several schemes were put forward or preventing floor heave in different supporting conditions. And the method of numerical simulation was used to make comparisons for stress and deformation characteristics of floor heave under the various supporting conditions on the basis of computing result. In addition， according to the results of numerical simulation and the prevention mechanism of floor heave， the optimum treatment scheme for floor heave in +600 m main haulage roadway could be obtained. Therefore， it has reference significance for preventing rheological type floor heave due to swelling and squeezing.