Abstract: Production mechanism and calculation method of ¹⁴C in EPR has been introduced in the paper. The normalized emission range of gas phase ¹⁴C is obtained by statistical analysis of large amount of gas phase ¹⁴C emissions from Siemens PWR, and the total amount of ¹⁴C in liquid phase and solid waste is further evaluated. The results show that the annual expected and maximum discharge ranges of ¹⁴C from EPR reactor are respectively 331 GBq/a and 660-700 GBq/a for gaseous discharge, 30 GBq/a and 60GBq/a for liquid discharge, and 64GBq/a and 130GBq/a for solid waste. The calculated gaseous ¹⁴C discharge with 10 ppm dissolved nitrogen in the primary circuits agrees well with the median value in Siemens/KWU PWRs. It reveals that the dissolved nitrogen concentration in the primary circuits is much less than the saturation concentration in volume and control tank covered by nitrogen gas during normal operation. The approaches used and conclusions are also important to the third generation nuclear power plants, including EPR and HPR1000.