Qijue 棋訣 (also written 碁訣 or 棊訣) "Explanations to chess" is a short treatise on Chinese chess written during the Southern Song period 南宋 (1127-1279) by Liu Zhongfu 劉仲甫 (fl. 1094), courtesy name Fuzhi 甫之. Liu hailed from Qiantang 錢塘 (modern Hangzhou 杭州, Zhejiang), of whose life is not much known. Another one of his books on chess, Qishi 棋勢, has not survived. Although Liu Zhongfu is known as a champion of the boardgame, there were also occasions when he was beaten, as demonstrated in the books Chunzhu jiwen 春渚紀聞 and Tieweishan congtan 鐵圍山叢談.
His book Qijue has four chapters, speaking on allocation (buzhi 布置), attack (qinling 侵凌), "battle" (yongzhan 用戰) and "conquest" (qushe 取舍). At the end of the book, the last chapter of Yan Tianzhang's 晏天章 (c. 1350) book Qijing 棋經 is added, Lunqi zashuo 論棋雜說, to which Liu Zhongfu has added some comments.
The Qijue is included in the series Mohai jinhu 墨海金壺 and Zhucong bielu 珠叢別錄, as well as in the encyclopaedia Yongle dadian 永樂大典.