Abstract: Based on analysis of the flow behaviors of foam fracturing fluid and the overall influences of fluid gravity, terrestrial stress gradient and terrestrial stress difference on fracture extension, two mathematical models are built up including a 3-D fracture extension model for flow of foam fracturing fluid in fractures and a distribution model of temperature, pressure and foam quality of foam fracturing fluids and the numerical calculation methods are also presented. The calculation results show that the solving methods presented can accurately simulate the flow of foam fracturing fluids in fractures and ate suitable for use in field foam fracturing design.