The invention discloses a gate type radioactivity monitoring and identification system, comprising a portal frame, wherein a gamma detector, a neutron detector, a nuclide identification detector, an alarm device, a power supply and a main control board are arranged on the portal frame; the nuclide identification detector is detachably fixed to the portal frame; the gamma detector, the neutron detector, the nuclide identification detector and the alarm device are electrically connected to the main control board; and the power supply is electrically connected to the main control board. The gatetype radioactivity monitoring and identification system disclosed by the invention can simultaneously monitor radioactive substances of radiation neutron rays and gamma rays and can perform nuclide identification, and the nuclide identification detector can be switched between fixed detection and hand-held detection for use according to onsite requirements.