The details of the design and implementation of a narrow linewidth, wavelength-tunable and variable repetition-rate short pulse Q-switched fiber laser are discussed. A traveling wave model is used in conjunction with Finite different time domain method to account for propagation delays, spatial distribution of powers and population densities in the laser. A tunable repetition rate and tunable wavelength laser is demonstrated experimentally, yielding pulses of peak power 7.1 W, width 212 ns (at 1533 nm) and a repetition rate of 10 kHz. The paper further discusses the simulation and experimental results of the characteristic features of tunable wavelength and tunable repetition rate pulsed laser. © 2013 Copyright SPIE.