The invention discloses a thickener which comprises a bin and at least two raking frames. The bin comprises a cylindrical portion and at least two conical portions, the upper ends of the conical portions are connected with the lower end of the cylindrical portion, the lower end of each conical portion is provided with a sand placement port, an inner cavity of each conical portion is communicated with that of the cylindrical portion, and the raking frames are correspondingly arranged in the conical portions respectively to stir materials in the conical portions. According to the thickener, the conical portions are arranged, so that the thickener has the advantages of high treatment capability, good concentration effect and lower height and is suitable for filling facility needs of ten-million-ton mines, and investment and occupied area can be reduced remarkably.