The hidden algebraic structure behind the BCJ relation has been speculated ever since its discovery. More evidence arise as our knowledge for BCJ relation deepens. Especially when lifted to string level, BCJ relation emerges naturally from the braiding of vertex operators. Moreover the fact that string BCJ numerator has a q-deformed commutators representation suggests the relation between BCJ relation and quantum algebra. In this talk, I will explain how Nichols’ algebra provides a framework to understand the algebraic structure behind BCJ relation.