Drawing on Asian contexts of principal-principal (PP) conflicts, for example, influence from controlling families and low dividends, this study examines whether external audit is an effective disciplining agent in a firm's tax avoidance, compared with foreign-ownership contexts. An analysis of 450 Korean firms indicates that the regulatory role of the 'Big-4' audit firms is negatively moderated by the controlling family, consequently increasing tax avoidance. In contrast, foreign ownership decreases tax avoidance, unaffected by the controlling family. It is therefore suggested that to control PP conflicts in Asian contexts, more attention should be paid to a firm's ownership structure.