Abstract: In order to get high single pulse energy with 100ps pulse width, a mode-locked Yb-doped picosecond fiber laser was designed and 100ps laser pulse was output. Master oscillator power amplifier (MOPA) with two-stage all fiber structure was adopted. In the preamplifier, gain medium was double-clad Yb-doped fiber with 7m core diameter and average power of stable pulse output was 160mW. In the master amplifier, gain medium was double-clad Yb-doped fiber with 20m core diameter and its output power was 16.60W while pump power increased to 35.37W. The corresponding single pulse energy was 1.63J and peak power was 16.61kW. And then, output laser of master amplifier was injected into photonic crystal fiber of 4.6m core via a home-made mode field adapter. 2.85W output power of white light supercontinuum was obtained and the supercontinuum spectrum wavelength covered the measured range from 600nm to 1700nm. The results show that this laser can be used for the generation of supercontinuum spectrum sources.