Large-area portable Beta surface contamination monitor

The utility model discloses a large-area portable Beta surface contamination monitor, which comprises optical organic glass, wavelength conversion optical fibers, a plastic scintillator, an incidence window and a photomultiplier, wherein the plastic scintillator is the thin slice type plastic scintillator, the incidence window is arranged above the plastic scintillator, the optical organic glass is lined below the plastic scintillator, the wavelength conversion optical fibers are embedded on the organic glass side by side, silicone oil is uniformly coated on the optical contact surface, an output end of each of the wavelength conversion optical fibers is connected with a plastic transmission optical fiber, an aluminum reflection layer is plated at the blind end of each of the wavelength conversion optical fibers, all plastic transmission optical fibers are converged to form an optical cable, and the optical cable is in butt joint with the photomultiplier by a flange. The utility model provides the large-area