[en] A set of quartz crystal microbalance (QCM) was installed in HL-2A tokamak to measure the material deposition of carbon and its compounds. In the experiments, the mass deposited in each shot is usually in the magnitude of 0.1∼10 μg, an increase or decrease of the mass deposited could be induced by re-erosion and sputtering, which needs further investigation. The results also indicate that more mass can be deposited on the QCM after disruption. In addition, the average thickness of deposited layer in each shot is estimated to be 10 nm in HL-2A tokamak. (authors)