The power consumption for agitating viscoelastic fluids including Boger fluids and Newtonian fluids in the laminar regime were compared for the inner-and-outer helical ribbon-anchor and the four helical ribbon-anchor impellers. The influence of elasticity on power consumption is significant. For Boger fluids the power consumption could be up to 1.5 times of that fro Newtonian fluids.The power consumption correlations:for agitating Newtonian

pseudoplastic and viscoelastic fluids was developed by means of a second-order elastic fluid rheological model. The parameters f_v

f_s and F~*_(1av) were determined experimentally. The predicted results agree with experimental data.