An all-normal-dispersion mode-locked Yb-doped fiber laser with wide spectrum was investigated. The stable mode-locking is realized based on the nonlinear polarization evolution. At the pumping power of 500 mW, the power of mode-locked laser can produce more than 130 mW output at the repetition rate of 28.1 MHz with pulse duration of 3.8 ps. In order to explore the spectral characteristics of all-normal-dispersion laser, the cavity is implemented by splicing the 50-m single mode fiber and by removing the birefringent filter. Under the pump power of 500 mW, the stable dissipative solitons are obtained with 90 mW output power, 3.58 MHz repetition rate, 519 ps pulse duration and spectrum ranging from 1 005~1 140 nm.