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The double tearing mode (DTM) in a high βN (βN ＞ 1.5) discharge with intal transport barrier on EAST was investigated.A 15 kHz tearing mode (TM) (m ≥ 3,n =3) appears at outer q =2 surface at first,which is stable in the high βN phase.Then a 2 kHz TM (m =2,n =1) occurs at inner q =2 surface.Soon after,high βN collapsed with the crash of ELM,and DTM formed during the collapse of βN.The positions of the two islands of the DTM are consistent with the q =2 surface.The temperature fluctuations are the strongest between the two magnetic islands.A statistical analysis of high βN discharges operating with the reversed magnetic shear configuration in the EAST 2015-2018 campaign revealed the existence of the DTM in many discharges.During the DTM phase,all βN are reduced by 10％-30％ within 0.1 s.However,there are two different βN behaviors thereafter-with and without βN recovery.Studying the physical mechanism of βN recovery during the DTM phase will benefit steady-state operation with reversed shear configurations in the future.