To meet the application requirements of terrestrial/space radiometric calibration and solar/atmospheric remote sensing measurement, a high precision spectral radiometer based on Gershun tube is developed. A design for Gershun tube spectral radiometer is introduced, and the spectral responsivity, spatial response uniformity, angular response property and inside and outside field-of-view radiation response characteristic of the Gershun tube spectral radiometer are tested. The Gershun tube spectral radiometers based on detector standard and spectral irradiation source standard are compared, and the standard uncertainty range is analyzed. Experimental results show that the spectral response repeatability of the Gershun tube spectral radiometer is 0.3%, the regional responsivity uniformity is 0.3%, the consistency of angular response and expected cosine distribution is 0.2%, and the radiation suppression ability outside field-of-view is 2.1×10-4. Standard uncertainty of comparison between Gershun tube radiometer and spectral irradiation source standard is 2.83%, and the consistency of experimental result and theoretical result is 0.17%. The designed Gershun tube spectral radiometer can meet application requirements.