PET insert for the existing MRI systems can be a potential affordable alternative of body PET/MRI system. To avoid mutual interference between PET front-end electronics and the MRI system, PET front-end (F/E) electronics are enclosed in RF shielded Faraday cage that is connected to the RF ground for shielding purpose. On the other hand, strip transmission line RF coil requires a grounded plane in parallel with a strip conductor as coil that are connected by shunt capacitors. In this study, we proposed a strip transmission line coil that replaced the ground one layer conductor with the shielded PET detector module. The combined system shows promise for a compact PET/RF coil modality as insert for simultaneous PET/MR imaging with existing MRI systems, suitable even at ultrahigh field MRI.