ThecoincidenceofGISTandothergastricmalignanciesaredocumentedwellbut arisingGISTfromcongenitalanomaliesisstillrarityinliterature.Todate,only a few papers have been concerned on the possibility of arising neoplasms from duplicationcystofgastrointestinaltract.There,aredominatingusualcancers,neuroendocrinecancersorlymphomasbutGISThasbeennotedonlyonce.Here,we report a case of 73 years old female-patient with typical gastric stromal tumor comprisedcentrallylockedanincompleteduplicationcyst.