Differences in Korean and English negative polarity questions (NPQs) are revealed by the interpretation of simple yes-no answers to them. Yes-no answers to NPQs have seemingly unpredictable interpretations (Claus et al. 2017, Holmberg 2013, Kim 2017, Krifka 2017, Kramer & Rawlins 2009, Ladd 1981, Sudo 2013). However, one clearly observable fact is that yes-no answers to English and Korean NPQs can have opposite interpretations. This study: (i) compares the interpretation of positive and negative polarity questions (PPQs and NPQs) in English and Korean; (ii) examines the structure of negation in each language and its interaction with NPQs; and (iii) reports on an online experiment which gathered native speaker interpretations of NPQs in each...