This paper reports on a passively mode-locked ytterbium-doped fiber laser with a 1502-m total cavity length operating in the dissipative soliton resonance (DSR) region using the nonlinear optical loop mirror (NOLM) technique. High-energy square pulses with an ultra-low repetition rate of 133.18 kHz are observed. Both the duration and single pulse energy of the output DSR pulse increase linearly with increasing pump power. The maximum output pulse duration reaches 761.6 ns at a pump power of 414.47 mW, while the single pulse energy at the same power level reaches 60.2 nJ. In addition, the influence of cavity length on the pulse duration and single pulse energy is investigated by changing the length of the single mode fiber in the NOLM. The results indicate that the longer the cavity length is, the larger the pulse duration is, and the lower the peak power is.