The Chinese National Compound Library (CNCL) held its duplicate exclusion meeting on June 4, 2014 in Shanghai. Fourteen representatives from CNCL core facility and six satellite libraries attended the meeting. Drs. Ming-Wei Wang and Fajun Nan (Director and Deputy Director of CNCL, respectively) proposed the key principles and overall arrangement of this work. The attendants discussed in detail about the propositions and suggested implementation plans of their own. As a major task for 2014, CNCL intends to complete the sample duplicate exclusion for its entire collation by the end of June.