Experiment 18 Ne+197 Au was performed in Heavy Ion Research Facility Radioactive Ion Beam Line at Lanzhou (RIBLL).The nuclear energy levels of 18 Ne were built by complete kinematical reconstruction of the decay products and diproton decay were observed from 18 Ne excited states.At 6.15 MeV,the experimental relative momentum and angular correlations of the emitted protons are given. The obvious enhancement at |qrel| =23 MeV/c and θc.m.= 40° shows the experimental criterion of 2 He duster decay from 18 Neq.