A replication-defective, recombinant oncolytic adenovirus encoding human endostatin with potential antineoplastic activity. Endostatin, a 20 kDa C-terminal proteolytic fragment of collagen XVIII, is an important angiogenesis inhibitor. Upon intratumoral administration, the adenovirus infects and replicates in tumor cells. The expressed endostatin may inhibit endothelial cell proliferation and angiogenesis which may result in a reduction of tumor growth.