An edge-colored graph G is conflict-free connected if any two of its vertices are connected by a path,which contains a color used on exactly one of its edges.The conflict-free connection number of a connected graph G,denoted by cfc(G),is defined as the minimum number of colors that are required in order to make G conflict-free connected.In this paper,we investigate the relation between the conflict-free connection numberand the independence number of a graph.We firstly show that cfc(G) ≤ α(G) for any connected graph G,and give an example to show that the bound is sharp.With this result,we prove that if T is a tree with △(T) ≥ α(T)+2/2,then cfc(T) =△(T).