With the development of nanotechnology, a variety of nanomaterials, gold nanoparticles (GNP) in particular, are gradually involved in tumor imaging and therapy. GNP at the molecular level can overcome the biological barriers to pool in tumor cells with priority, and carry the detection signal or drugs to specifically recognise tumor cells through coupling with tumor-specific markers. Meanwhile, GNP have special physical properties, which will bring new breakthroughs to tumor diagnosis, treatment and monitoring.