This paper proposes a language specification that enables users to make contents for communication robots and share the contents widely among users. Such a language specification has to meet following three conditions. First, users can share the contents widely. Second, users can make the contents easily in a high abstract level. Third, robots can select contents to present through a communication with human. However, no ordinal researches satisfies all these three conditions. Therefore, this paper proposes a language specification called Robot Communication Markup Language (RCML) that enables users to make communication contents of communication robots and share those contents widely among users. RCML enables users to describe motions and sensor events of communication robots in a high abstract level.