A positron emission tomography (PET)-magnetic resonance imaging (MRI) convergence system. In one aspect, the invention may be a PET-MRI convergence system including: a cylindrical magnet bore which includes an outer wall and an inner wall; a gradient magnet which is disposed adjacent to the inner wall of the magnet bore; a MRI RF coil which is disposed adjacent to the inner wall of the gradient magnet, emits an RF pulse signal and detects MRI data corresponding to the RF pulse signal; and a PET detector which is spaced apart from the MRI RF coil and is disposed adjacent to the inner wall of the gradient magnet, and detects PET data.