Polymer flooding characteristics of partially hydrolyzed polyacrylamide (HPAM) solution with the addition of NaOH were examined in homogeneous glass-bead packs. The heavy oil recovery in unconsolidated sandstone formations by applying the alkali-polymer flooding was observed. Experimental results showed that HPAM solution was sensitive to temperature, salinity, and alkali, finding that alkali-polymer solutions are more effective in improving viscosity than conventional polymer solutions. The solution of 0.5 wt % NaOH mixed with 1500 ppm HPAM (12 mol % hydrolysis degree) was found to be the optimal choice, which gives rise to the highest viscosity on the rheological characterization. Flood tests using the alkali-polymer solution showed an increase in oil recovery by 30% over water-flooding when the water-cut reached 95%, indicating that alkali-polymer could be more effective in improving sweep efficiency than polymer flood. (c) 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013