To study the effect of drilling fluid rheological property at low temperature, there is great significance to ensure the safety of gas hydrates drilling in permafrost area developed smoothly. Through the rheological property comparison with solids-free polymer drilling fluid and low-solids polymer drilling fluid, the change rule of rheological property between the two types of drilling fluids at low temperature have analyzed. The parameters of Herschel-Buckley model are adopted to analysis and comparison the rheological property with solids-free and low-solids polymer drilling fluid, and the mathematical model about relationship of viscosity with temperature have built of the two types of drilling fluids, The measured data validation show that the fit of the mathematical model is high, and it can adopt different mathematical model to analyze different types drilling fluids on worksite. Microscopic mechanism analysis of rheological property of two types drilling fluid have done by using SEM.