The highly developed honorific systems in Korean and Japanese are functionally similar but differ with respect to non-subject referent honorifics, which indicate the speaker’s deference toward a non-subject referent participant in the event described. Korean expresses non-subject referent honorifics lexically, whereas Japanese expresses them morphologically. Moreover, the Korean pattern of non-subject referent honorifics is limited to a handful of verbs while the Japanese pattern is fairly productive. This paper compares expressions of honorifics for objectively identical situations in the two languages and argues that their different usages and productivities are motivated by socio-cultural factors.