It is an object of the present invention to provide a targeting agent, which enables the delivery of a drug to tumor sites or the imaging of tumor sites by utilizing its effect of accumulating to such tumor sites. The present invention provides a targeting agent for tumor site, which comprises a hydrophilic polymer-modified carrier coated with a gelatin-like protein that has repeats of a sequence represented by Gly-X-Y characteristic to collagen and has two or more sequences of cell adhesion signals in a single molecule wherein X and Y each independently represent an amino acid and a plurality of Gly-X-Y sequences may be the same or different.
