To provide a device for measuring and classifying a crystal piece which can safely and stably supply and convey a very thin crystal piece without breaking and chipping it in a process of supply and conveyance.

In this device for measuring and classifying a crystal piece, a ball feeder 5 and a straight advancing feeder 4 are horizontally arranged, and a tilt angle of a crystal piece run face of the ball feeder 5 and a tilt angle of a crystal piece run face of a straight advancing feeder shoot 2 are inclined at the same angle (35 to 45 degrees). A rotation conveying part arranges the rotational center axis inclined so as to place a lower end face of a sucker nozzle 6 rotated with a rotary shaft serving as the center in parallel to the crystal piece run face of the straight advancing feeder shoot 2.