(Amended) A media-agitation type pulverizer comprising: a pulverization container including an end plate closing up an upper end thereof and having an upright cylindrical pulverization chamber containing pulverizing media in the form of beads; a raw-material-slurry supply port provided in the pulverization container; an agitating member disposed in a bottom region of the pulverization chamber and having a rotary shaft substantially coaxial with a central axis of the pulverization chamber; a media separation member provided within the pulverization chamber and above the agitating member, and a guide ring installed to radially divide a lower region of the pulverization chamber into an inner section and an annular outer section, whereby a flow of a mixture of the raw material slurry and the pulverizing media is formed as a helicoidal flow comprising a combination of a primary flow flowing in a circumferential direction of the pulverization chamber and a secondary flow flowing through a circulation flow path which has an upward flow path and a downward flow path created, respectively, in the outer section and the inner section of the lower region of the pulverization chamber, with respect to the guide ring; the media-agitation type pulverizer being characterized in that it further comprises rotational-flow suppressing means provided within the pulverization chamber and adapted to control the helicoidal flow to suppress the primary flow while strengthening the secondary flow, thereby stabilizing the helicoidal flow, the rotational-flow suppressing means being formed in a cruciform shape, and provided in the guide ring, and the guide ring with the rotational-flow suppressing means being provided above the agitating member. a pulverization container including an end plate closing up an upper end thereof and having an upright cylindrical pulverization chamber containing pulverizing media in the form of beads; a raw-material-slurry supply port provided in the pulverization container; an agitating member disposed in a bottom region of the pulverization chamber and having a rotary shaft substantially coaxial with a central axis of the pulverization chamber; a media separation member provided within the pulverization chamber and above the agitating member, and a guide ring installed to radially divide a lower region of the pulverization chamber into an inner section and an annular outer section, whereby a flow of a mixture of the raw material slurry and the pulverizing media is formed as a helicoidal flow comprising a combination of a primary flow flowing in a circumferential direction of the pulverization chamber and a secondary flow flowing through a circulation flow path which has an upward flow path and a downward flow path created, respectively, in the outer section and the inner section of the lower region of the pulverization chamber, with respect to the guide ring; rotational-flow suppressing means provided within the pulverization chamber and adapted to control the helicoidal flow to suppress the primary flow while strengthening the secondary flow, thereby stabilizing the helicoidal flow, the rotational-flow suppressing means being formed in a cruciform shape, and provided in the guide ring, and the guide ring with the rotational-flow suppressing means being provided above the agitating member.