The purpose of this study is to analyze how Korean and Japanese use disagreements and negative assessments to frame their actions a joke, and to examine the differences in framing strategies in natural conversation between friends. I have found the following differences between Korean conversations and Japanese conversations: (A) In Japanese conversation speech level shifts and formulaic expression were used as contextualization cues that signal a joke while Korean used personal pronoun shifts and in some case, negative assessments were uttered without apparent contextualization cues. (B) To avoid the possibility that their utterance is regarded as a face-threatening act, Japanese speakers shift a frame by clearly expressing that their utterance is a joke. As a result, hearers participate in the joke frame without being misled. On the other hand, Korean speakers frequently utter negative assessments without apparent contextualization cues and tend to rely on how hearers interpret the frame.