Based on two popular theoretical frameworks regarding media choices of rational choice and social influence (Markus 1987; Trevino et al. 2000) the main theme of this paper is to investigate applicability of these frameworks on a case where the pattern in usage and collective meaning of a medium is shaped in the cultural context. Focusing on the phenomenon of many Asians preferring not to send electronic mail to their supervisors, we compared media choice behaviors in the upward channel between a U.S. and a Korean organization. The empirical results suggest that the theories based on those frameworks are not sufficient to explain the phenomenon of individuals not sending electronic mail to their supervisors in the Korean organization. As a result of the study, we reconsider and refine those previous theories in such a way that we ask questions like (1) when is the rational choice model more pronounced than social influences in choosing a medium, and (2) how do rational choices and social influences interact through social symbolisms constructed in one particular organization? We believe that this research plays an important role in further extending our knowledge on media choice, and thus managers’ communication issues.