A harmonic dark pulse generation in an erbium-doped fiber laser is demonstrated based on a figure-of-eight configuration.It is found that the harmonic dark pulse can be shifted from the fundamental to the 5~(th) order harmonic by increasing the pump power with an appropriate polarization controller orientation.The fundamental repetition rate of 20 kHz is obtained at the pump power of 29 mW.The highest pulse energy of 42.6nJ is obtained at the fundamental repetition rate.The operating frequency of the dark pulse trains shifts to 2~(nd),3~(rd),4~(th) and5 th harmonic as the pump powers are increased to 34 mW,50mW,59 mW and 137 mW,respectively. A harmonic dark pulse generation in an erbium-doped fiber laser is demonstrated based on a figure-of-eight configuration. It is found that the harmonic dark pulse can be shifted from the fundamental to the 5 th (th) order harmonic by increasing the pump power with an appropriate polarization controller orientation. The fundamental repetition rate of 20 kHz is obtained at the pump power of 29 mW. The highest pulse energy of 42.6 nJ is obtained at the fundamental repetition rate. The operating frequency of the dark pulse trains shifts to 2 ~ (nd), 3 ~ (rd), 4 ~ (th) and 5 th harmonic as the pump powers are increased to 34 mW, 50 mW, 59 mW and 137 mW, respectively.