A double pulse dissipative solitons (DSs) passively mode-locked Yb-doped fiber laser with a tunable wavelength is proposed and demonstrated in the all-normal-dispersion (ANDi) system. Using a Sagnac loop as a tunable all-fiber format spectral filter and the effect of nonlinear polarization evolution (NPE) as the mode-locking mechanism, a stabilized double pulse DSs mode-locked pulse output is obtained in the ANDi Yb-doped fiber system. When the polarization state of the Sagnac loop changes, the tuning of the double pulse DSs output spectrum is realized with a tuning range of 1038.96-1044.80 nm. Furthermore, by changing the pump power of the laser cavity, the pulse-spacing of the double pulse can be changed from 0.034 μs to 0.021 μs. Under the pump power of 520 mW, the double pulse DSs pulse has the maximum energy of 34.3 nJ and the repetition rate of 2.285 MHz.