Quenching rate is an important factor in radiation quenching studies of porcelains. It is also important for TL predose dating, as low quenching rate leads to large errors or render TL predose dating inapplicable. Radiation quenching rates of 78porcelain samples from Zhejiang Cixi Shanglin Lake were tested. These earliest celadon porcelains were from 11ancient Yue sites of the Tang, the Five dynasties and the Song. The average radiation quenching rate of Yue porcelain samples is 11.4%, which ensures separation of different sensitivity curves and high accuracy of TL ages by the pre-dose quenching technique.