A kind of chair back linkage includes that a base unit has an articulated section； One backrest is pivoted the what base unit； One continuous action base slides the what backrest； One connection rod set has a first connecting rod and a second connecting rod, which is pivotally connected the what second connecting rod, and the first connecting rod and second connecting rod are pivotally connected the articulated section of the what base unit respectively and the continuous action base and one affect portion； One affects part to have what the portion of affecting affected the what connection rod set to affect portion.一種椅背連動裝置，包含有一基座單元具有一樞接部；一背架樞連於該基座單元；一連動座滑移於該背架；一連桿組具有一第一連桿以及一第二連桿，該第一連桿係樞接於該第二連桿，該第一連桿與第二連桿分別樞接於該基座單元之樞接部以及該連動座，以及一牽動部；一牽動件具有一牽動部牽動於該連桿組的牽動部。
