We present an all-fiber all-polarization-maintaining (PM) single mode (SM) fiber pulse nonlinear amplification system. The seed laser with a repetition rate of 200 MHz is amplified by two-section erbium-doped PM gain fibers with different peak-absorption rate. The amplified pulse duration can be compressed into 34-fs with 320-mW output power, which corresponds to 1.6-nJ pulse energy and approximate 23.5-kW peak power. In addition, the amplified and compressed pulse is further coupled into the high nonlinear fiber and an octave-spanning supercontinuum generation can be obtained. To the best of our knowledge, it is the highest peak power and the shortest pulse duration obtained in the field of all-fiber all-PM SM pulse-amplification systems.