Objective To evaluate the cancer risk among the inhabitants around a certain nuclear facility of Gansu Province after operation for nearly 50 years.Methods Specially developed forms were filled by countryside doctors in the villages 30 km on the leeward or at the lower reaches of Yumen City,Gansu Province where a nuclear facility had operated for nearly 50 years,to register the relevant data of those who died of solid cancer and leukemia during the period from 1 January 2004 to 31 December 2008 based on the relevant data and household survey.A town 90 km away from the nuclear facility with 4181 people were regarded as control area.Results The crude mortality and standardized mortality rate(SMR) of cancer were 95.51×10-5 and 93.56×10-5.respectively.The crude mortality and SMR of leukemia were 2.44×10-05 and 2.22×10-05, respectively.and the crude mortality and SMR of cancer were 106.88×10-05, and 89.31×10-5, respectively.The crude mortality and SMR of leukemia were 2.44×10-05 and 2.22×10-5, respectively in the investigated area,and the crude mortality of leukemia was 3.56×10-5 (only one leukemia cage died)in the control area in the same time.The cancer and leukemia mortality rates of the investigated area were similar to those of control area.Conclusions Nuclear facility does not significantly increase the cancer mortality among the residents living nearby.