The viscosity behaviors of polyacrylamide fracturing fluid had been studiede through investigating the concentration，temperature，pH and metallic ion .The results showed that,when increased the PAM concentration, the fracturing fluid viscosity increased, non-Newtonian viscosity enhanced and the viscosity of fracturing fluid could meet the construction requirements when the concentration was 1.0%. increased the temperature could decrease the fracturing fluid viscosity and weaken non-Newtonian. Change the PAM fracturing fluid pH environment also could decrease the viscosity. Metal ions could decrease the viscosity of fracturing fluid, the effect of metal ions on PAM viscosity order was Mg2+>Ca2+>Na+>K+, consisted with diffusion layer theory. The static suspension experiments showed that when the PAM concentration of 1% and 60 ℃,,the proppant-carrying time reached 16.58min/cm,,could meet the fracturing fluid carrying sand standards.