A grinder comprises: a receiving container, formed with an accommodation space and an installation space, and the bottom end thereof being extended with a connection ring have a feeding port, and a hollow grinding seat and a fasten ring are respectively and detachably disposed in the feeding port and the connection ring; an electric driving device, detachably disposed in the installation space; and a base, detachably disposed at the bottom end of the receiving container and including a hollow grinding chamber having the interior disposed with a support member with a pivotal shaft, a passive rod is sleeved and linked with a conical grinding disk, the top end and the bottom end of the passive rod are respectively sleeved with the output shaft and the pivotal shaft, thereby allowing the grinding disk to protrude into the grinding seat and forming a gap between the above two.