Coral reef ecosystems are characterized by high primary production and biodiversity, providing rich biological resources and valuable ecosystem goods and services for humans. Reef-building corals survive in coastal areas near several nuclear power plants in China. Additionally, coral islands can potentially support future applications of floating nuclear power plants in remote marine environments for energy supply. Although artificial radionuclides derived from nuclear power plants are released into coral reef ecosystems, there is limited information on the biogeochemical behavior of artificial radionuclides and their radiological impacts on coral reef ecosystems. In this study, key artificial radionuclides, including ¹⁴C, ^239+240Pu⁹⁰Sr, ²³⁶U, ¹²⁹I, and ¹³⁷Cs, were carefully selected and comprehensively investigated from the perspectives of activity concentration, coral skeleton-seawater distribution coefficient (K_d value indicating the ability of enrichment), and radiation dose rates derived from the ERICA model. Based on our previous studies on ¹⁴C, ⁹⁰Sr, and ¹³⁷Cs in coral reef ecosystems, we reviewed and analyzed the research progress on key artificial radionuclides, which were classified into low-level (K_d ≤1 L/kg), medium-level (1 L/kg<K_d <1 000 L/kg), and high-level (K_d ≥1 000 L/kg) enrichment groups according to the Kd value. The Kd values were ranked in descending order as ¹⁴C>^239+240Pu>⁹⁰Sr and ²³⁶U>¹²⁹I>¹³⁷Cs. The radiation dose rates of the above-mentioned artificial radionuclides and naturally occurring radionuclides of ²¹⁰Po in coral polyps were simultaneously calculated using the ERICA tool and ranked in the order ¹⁴C>⁹⁰Sr>¹³⁷Cs> ^239+240Pu>²³⁶U>¹²⁹I. The total radiation dose rate of artificial radionuclides was estimated to be 4.73×10^-4 μGy/h, which was much lower than the radiation dose rate of ²¹⁰Po (6.60 μGy/h) and the screening benchmark level of no effect (10 μGy/h). Therefore, artificial radionuclides in the surface seawater of the South China Sea should not pose significant radiological risks to coral polyp populations. Overall, our results provide technical support for the assessment of nuclear safety in coral reef ecosystems in the context of the potential application of floating nuclear power plants in coral islands in the South China Sea.