Composite rock breaking diamond bit

The invention discloses a composite rock breaking diamond drill bit which specifically comprises a drill bit body and a blade extending out of the drill bit body, cutting teeth are fixedly installed on the blade, at least one of the cutting teeth is a rolling scraping tooth, and the rolling scraping tooth is composed of a scraping unit and a rolling unit. The rolling unit is installed on the scraping unit in a rotating connection mode, the rolling unit and the scraping unit form a rolling and scraping combined rock breaking mode for rock, and the scraping unit is fixed to the blade. When the drill bit drills in a stratum with strong abrasiveness and high hardness, the problems that the drill bit loses efficacy quickly and the rock breaking efficiency is low due to abrasion of tooth edges of the cutting teeth are solved, and the purposes of relieving abrasion of the cutting teeth, prolonging the service life of the drill bit, assisting in rock breaking of the PDC teeth and improving the rock breaking efficienc