An all-optical tunable fiber filter with dual graphene films enabled by a fiber open microcavity is presented. The graphene films are deposited on the fiber end surfaces via the light induced thermophoresis effect. Two fiber end surfaces deposited with the graphene films are used to construct the microcavity. Under an additional 980-nm optical pump, the filter experiences stronger optical Kerr effect and photothermal effect since the light propagates to the dual graphene films repeatedly. Experimental results show that its all-optical tunable wavelength range can reach 8.295 nm within the optical pump power range of 0~80mW, and it is almost 23.8 times of the reported all-optical tunable Fabry-Perot filter. IEEE