The aim of this research is that a robot comforts a human to improve his/her mental state. It is known that human's facial expression is one of the triggers of arousing emotion. In this paper, as a means to comfort a human, we propose a method of predicting what kind of facial expression will appear. With this method, a robot selects an action which is expected to elicit a specific facial expression, based on the result of predicting human's facial expression. We performed experiments of eliciting a specific facial expression with Mof-mof robot. Mof-mof robot selected some actions which are expected to elicit designated facial expressions such as 'happy,' 'surprised,' 'angry' and 'sad' from four subjects. Some subjects' facial expressions seemed to be elicited by robot's action. Results of the experiments show that easiness of eliciting a specific facial expression seems to be affected by the type of the facial expression and human's will.