This paper demonstrates the relationship between ethnomethodology and Max Weber's sociology. Ethnomethodology has often been criticized by other sociologists for its research policy and attitudes. To counter such criticism, first we try to verify the affinity between ethnomethodology and the classical sociology discussed by R.A. Hilbert. Second, we demonstrate, through Garfinkel's doctoral dissertation, that Hilbert's discussion of affinity is problematic. Finally, we reconsider the significance of ethnomethodological research through an argument on the affinity between ethnomethodology and Weber's sociology.