Abstract: AlCoCrFeNi_2.1 eutectic high entropy alloy combines the advantages of high entropy alloy and eutectic alloy to achieve a favorable strength and plasticity. Trace Re helps to improve the eutectic structure in the alloy and the tensile strength of the alloy is enhanced significantly. The effects of rolling and heat treatment on the microstructure and properties of eutectic high entropy alloy AlCoCrFeNi_2.1Re_0.5 were investigated. The results show that the strength of the alternately rolled samples is greatly improved due to the reduction of lamellar spacing and the formation of fine dispersed B2 phase. After high temperature annealing, the plasticity of the alternately rolled specimens is obviously improved.