Abstract: To identify metal uranium components with same geometry and mass but different enrichments, ²⁵²Cf source noise analysis was used to gain the neutron time correlation coincidence measurement. Based on the analysis and processing of neutron time correlation coincidence measurement, the characteristic parameters are determined. Through the method of BP neural network, we determined the ²³⁵U enrichments of same geometry and mass but different enrichments uranium components. Result shows that by the method of BP neural network, we can diagnose the ²³⁵U enrichments effectively.