Abstract: Provided is a kind of modified recombinant human endostatin that has the structure of CH3O—(CH2CH2O)m—CH2CH2CH2—N?H-Endostar, wherein the average molecular weight of CH3O—(CH2CH2O)m—CH2CH2CH2— is 20-40 kD. The modified recombinant human endostatin enhances the stability in vivo, improves blood drug concentration, prolongs half-life, markedly increases the activity of inhibiting the endothelial cells proliferation, thus reduces drug dosage and decreases administration frequency. Its application for preparing anti-tumor pharmaceutical compositions is also provided.