The accident source term and radiological consequence evaluation of small heating reactor at site boundary is the key content of nuclear and radiation safety review. According to the design characteristics of the advanced small reactor, the accident source term calculation model is established for fuel handling accident to study the release of radionuclides after the accident. Based on the experience of accident radiological consequence analysis of small reactor abroad and ARCON methodology in RG4.28, the atmospheric dispersion factor and individual dose at site boundary in fuel handling accident are analyzed. The results show that two hours after the accident, the radionuclides in the fuel cladding gap release into the environment, and the release amount of radionuclide in the environment reaches the radioactivity level of 10¹⁴ Bq. The release amount of inert gas is higher than that of iodine, and that of ¹³³Xe is the largest. The individual effective dose and thyroid dose at the site boundary after 30 days of the fuel handling accident are within the dose limits and the maximum dose occurs at the east-north-east direction. The results of the accident source term and radiological consequence could provide technical support for offsite dose assessment and review of the advanced small reactor.