The invention belongs to the field of medicines, and particularly relates to an alpha-cyano-alpha, beta-unsaturated amide compound with a structure in a formula (I), and a stereisomer or a pharmaceutically acceptable salt thereof, and an application of the alpha-cyano-alpha, beta-unsaturated amide compound in anti-tumor. A pharmacological experiment result proves that the compound has an excellent inhibiting effect on an epidermal growth factor receptor (EGFR) and a mutant of the epidermal growth factor receptor, and is capable of inhibiting multiplication of a plurality of tumor cells, so that the alpha-cyano-alpha, beta-unsaturated amide compound can be applied to preparation of anti-tumor medicines as an EGFR kinase inhibitor. The formula is shown in the description.