The invention discloses an imaging device for flaky materials and a sorting machine. The imaging device for the flaky materials comprises a belt conveying unit, an imaging unit and a locating suction disc sucking the flaky materials. A single set of belt of the belt conveying unit penetrates through the position between the locating suction disc and the imaging unit. The locating suction disc and the imaging unit are fixedly mounted on the two sides of the single set of belt of the belt conveying unit respectively in an opposite mode. A space allowing the flaky materials to pass through is reserved between the imaging unit and the single set of belt of the belt conveying unit. Air flow through holes allowing air flow to pass through are formed in the locating suction disc in the moving direction of the single set of belt of the belt conveying unit, and suction holes communicated with the air flow through holes are formed in the side, close to the imaging unit, of the locating suction disc in the direction perpendicular to the air flow through holes. According to the imaging device for the flaky materials and the sorting machine, other suction devices are omitted, the occurrence of the situations of skew, shaking and unevenness of the flaky materials in the transmission process can be avoided, the flaky materials can be flattened, shaking can be reduced, and the requirements of image detection can be met.