The invention relates to an erythropoietin mimic peptide derivative having a function of long-acting promotion of erythropoiesis. The invention also provides a preparation method of the erythropoietin mimic peptide derivative and an application of the erythropoietin mimic peptide derivative in preparation of drugs for treatment of diseases with deficiency of erythropoietin or erythrocyte group lacking or defects as characteristics. The erythropoietin mimic peptide derivative provided by the invention comprises a polypeptide as shown in SEQ ID NO:1, and has the structural general formula represented by the formula I, wherein two cysteines of the polypeptide form a disulfide bond, and an N tail end is acetylated. The SEQ ID NO:1 is defined in the specification.