The action theorists have been adopting the causal explanation especially in philosophy and the social sciences. This article discusses the causal explanation of action from the stand point of ethnomethodology and conversation analysis First, rethinking how the causal theory and anti-causal theory were developed in philosophy, I introduce Kuroda's critics of general causality and his original causal theory. He situated intentional action as the central concept of the action and wrote that the action is a certain change of the world caused by the human agency. According to him, when a human agency as the resource of causality exists, there is an actions. Second, I present an example in which Kuroda's causality can not be adopted clearly, and introduce the ethnomethodological point of view to the action and the causality. Ethnomethodology facuses on the natural language and considers the interaction and the description of action as a key situation in terms of the action. Kuroda stated the human agency is the key concept of the action, so his theory cannot avoid adopting causality to his action theory. It is true that members of society think and use the causal explanation as a feature of the settings, but in the ethnomthodological view, the causality and the actor emerge in the interaction especially in the sequential order of the activity. Finally, the mundane reasoning of causality is discussed, in which the work of specifying and understanding causality emerges "from within" the local sequence of the settings, as regards politics.