Permeability-blocking treatments with gels were simulated for a reservoir composed of two independent, homogeneous layers, each with traverse isotropic permeability. Horizontal permeability contrast between the layers ranged from 0.0033 to 0.5. Vertical/horizontal permeability ratios for both layers were the same and set between 0.001 and 0.1. Gel treatments were pumped into the high-permeability lower layer. Polymer floods/waterfloods entered both layers; allocation of the pumped fluid depended on the mobilities for each layer. Near-wellbore gel treatments increased oil recovery in cases of low vertical/horizontal permeability ratios by improving the injection profile. Under the conditions examined (equal layer thickness and 3-cp oil and 0.8-cp water viscosities), results were most beneficial in reservoirs with a horizontal permeability contrast of approximate to 0.05. Gel treatments placed in the reservoir at the near-wellbore region or deep in the reservoir were ineffective in cases of high crossflow.