In this paper, experimental investigation on two oil-soluble drag-reducing agents (DRAs) were carried out in stirred vessel by standard six-blade Rushton, based on the application of particle image velocimeter (PIV). Two DRAs (1# and 2#) with different concentrations from 3 ppm to 50 ppm were added into diesel, respectively, and speed of impeller speed was set 400 rpm. Flow field characteristics including turbulence intensity, turbulent kinetic energy (TKE), and energy dissipation rate (EDR) influenced by those additives in stirred vessel were studied. It was found that inhibition effect of turbulence intensity of the two DRAs is not obvious with concentration below 10 ppm. However, when concentration is above 10 ppm, turbulence inhibition effect becomes more obvious. Under low concentration, 1# has better turbulence inhibition effect in the area near impeller, while 2# has better turbulence inhibition effect under high concentration. When the two DRAs are under the same concentration of 50 ppm, turbulent flow energy and energy dissipation rate are obviously reduced.