The effect of ethanol on the ethylene consumption in fuel-rich, premixed, laminar, burner-stabilized flames at atmospheric pressure was investigated. A pure ethylene flame and three ethylene/ethanol flames with different ethanol fractions were simulated at the same equivalence ratio. The results showed that the different reaction rates for ethylene consumption in the flames were related to the reaction kinetics in these flames with an insignificant thermal effect. Changes in key radical concentrations in the flames were observed depending upon the initial ethanol mole fraction in the fuel, and the reaction pathways responsible for the production and destruction of ethylene were identified. The chemical behaviors differed significantly at different flame heights above the burner. At the flame height with a temperature of 769 K, a decrease in the OH concentration was responsible for the reduction in the reaction rate for ethylene consumption with the addition of ethanol. At the flame height with a temperature of 1470 K, the normalized ethylene concentration in the flames increased with the increase of the initial ethanol fraction in the fuel, the reason for which appeared to be the decomposition reactions into ethylene rather than the changes of species pool in the flames.