This research aims to know and to see the effects of Aceh society's understanding toward the decision in choosing Sharia bank (Study Case of Aceh Sharia Bank in Banda Aceh). The type of this research was a descriptive qualitative research using primer data. The result (answers) of quetionnaires from 52 respondents. The analysis used in this research was simple linear regression analysis. The researcher had done validity test and reliability test on the questionnaires' data. The result of the research showed that from the simple linear regression test, the understanding had significant effect toward the variable of choosing sharia bank. Yet, the effect was so minor, it was only 9,9 percents.