China repos trade in the over-the-counter interbank market as well as the stock exchange. This paper examines the behaviours, sources, and drivers of the spread between China’s exchange and interbank reporates from December 2006 to June 2018. After adjusting for different day-count quoting methods, I dissect the exchange to interbank repo spread into two components: cross-market segmentation between exchange and interbank markets for non-depository institutions (NDIs), and within-market counterparty segmentation between NDIs and depository institutions (DIs) in the interbank market. The 1-day repo markets are found to be more segmented, with the spread mainly driven by the cross-market segmentation for NDIs, reflecting the two different market mechanisms and trading frictions that prevent NDIs from effectively arbitraging across the two markets in the shorter tenor. On the other hand, the 7-day repo markets are found to be less segmented, with the spread mainly driven by the counterparty segmentation between NDIs and DIs within the interbank market, reflecting greater counterparty credit and liquidity risks for NDIs relative to DIs. Further analysis uncovers the impacts of quarter-end effect, monetary policies, and shadow banking activities on the cross-market and within-market segmentations in China’s repo markets.