A subnanosecond pulsed, one-stage Yb-doped fiber master oscillator power amplifier (MOPA) system for different pumping constructions is reported, which is seeded by a passively Q-switched NdYAG microchip laser. The comparison and discussions of average power, spectrum, together with pulse temporal profile of output laser under the forward pumping and backward pumping conditions are presented. Results show that the latter one provides the better performance, in which average output power as high as 9.3 W is achieved with pulse duration of 450 ps at 10 kHz repetition rate. The corresponding peak power is higher than 2 MW.